Invoking - Terminal Setup

When invoking the EarthPoint application (epts), terminal setup options are specified through the “--term” command-line option:
epts --term=SETUP_OPTIONS

Options may be specified in any order and in any combination.
Multiple options may be concatenated, seperated by commas (','):
If the argument string contains whitespace, enclose the entire argument string in single- or double-quotes.

Summary of Options

OPTION	DESCRIPTION
W option	stream Width
C option	Color attributes
A option	Ansi compliant
B option	input Buffering
L option	Locale name
P option	Panic button
S option	cursor Style

The term “Stream Width” refers to the character width for input and output streams for the application. Typically, the character width is either 8-bits (char) or 32-bits (wchar_t).

For console applications, the I/O stream width is established either directly by declaring the width or by locking in the character width with the first data read from, or written to the the I/O streams. Once locked in, the stream width cannot be changed without closing and re-opening the stream(s), which is not as straightforward as it sounds, and is therefore discouraged.

w - Use the wide (wcin/wcout) input/output streams. This is the default, and is strongly recommended.
n - Use the legacy narrow (cin/cout) input/output streams. The narrow I/O streams are not recommended for modern applications,
but may be used for testing the interface.

Example:
epts --term=W:w # set Wide stream width

To set this option directly, call the AnsiCmd method: acSetStreamWidth.

Specify the text foreground, and optionally the background color attribute(s). The foreground color argument is required, and the background argument is optional, and if not specified, the terminal default background will be used.

Within a console application, it is often useful, to use contrasting colors to draw the user’s attention to important information. For applications which include the AnsiCmd library, these color attributes may be specified as a command line option.

The -C option is used to specify one of the basic eight(8) colors (or default) for foreground and background.

Examples:
epts --term=C:r # set Red foreground with Default background
epts --term=C:cb # set Cyan foreground with Blue background
epts --term=C:dg # set Default foreground with Green background

To set this option directly, call the AnsiCmd method: acSetFgBg.

The most popular terminal emulator software, Gnometerm, Konsole and XTerm all support the core set of ANSI escape sequences. However, some terminal software may not understand some of the basic commands such as those which reset (disable) certain individual settings.

For terminals with this limited support, the AnsiCmd library functions can substitute the full reset command for the unsupported individual reset commands. While the full reset is slower and less convenient for the application programmer, it provides a way to produce a reliable application interface.

For example, the standard way to reset the Bold attribute is with the aesBOLD_OFF sequence:
acSetMod ( aesBOLD_OFF );
If this command or similar commands is not supported by the terminal, then the global attribute reset can be called:
acSetMod ( aesRESET );
This substitution is done automatically if the internal non-compliance flag is set.

The level of ANSI compliance is specified by:
y - Yes, the host terminal supports the common ANSI escape sequences.
This is the default, and should be correct in most cases.
n - No, the terminal is unable to handle some of the necessary sequences.
Use the reliable reset when disabling an attribute.

To set this option directly, call the AnsiCmd method: acFullReset.

Specify the buffering options for the input stream (stdin).

By default, keyboard input at the terminal prompt is stored in the stream buffer until the user presses the Enter key; however, application control of the keyboard input stream is, in the author’s view, critical to the success of the application.
(Our opinions are plentiful and provided free-of-charge.)

If your applications would benefit from having full control of keyboard input, then the -B option is used to specify the way keyboard input is captured, filtered and presented to the application.

To set this option directly, call the AnsiCmd method: acBufferedInput.

Specify the “locale” to be used within the application.

A locale is the set of rules used to interpret the way text and numeric data are processed and presented. A few examples of locale-dependent data are, currency values, telephone numbers, timestamps and measurements.

Two command-line options are available:

It is very likely that the terminal environment in which your console application runs specifies the locale via one or more environment variables. At the command line type:
echo $LANG
To list the types of formatting handled by the current locale, at the command line type:
locale
To list the UTF-8 compliant locales supported by your system, at the command line type:
locale -a | grep -i 'UTF'
This should yield a list of filenames such as
en_US.UTF-8, zh_CN.utf8, es_AR.utf8

Technical Note: Except for Windoze(tm), the civilized world uses UTF-8 character encoding exclusively. Be sure that any locale specified for use in your application is based on UTF-8 encoding.

Technical Note: If a console application does not explicitly specify a locale, the so-called “C-locale” is used. This is not actually a locale at all but the complete lack of a locale—resulting in a complete lack of coherent data formatting.

The Break Signal, otherwise know as the Panic Button or Control+C is the primary method of killing a console application which has locked up or has gone off into the weeds.

By default, the terminal receives the break signal and immediately kills the application, leaving your data in an indeterminate state.

This is fine if you don’t care about your data, but if you actually don’t care about your data, please step away from the keyboard — and pursue a career in marketing. Otherwise, your application may benefit one of these options.

Please see Capturing the Break Signal for additional information.

To set this option directly, call the AnsiCmd method: acCaptureBreakSignal.

Specify the shape and animation (blinking or steady) of the visible cursor.

To set this option directly, call the AnsiCmd method: acSetCursorStyle. Note that this method may also be used to set cursor as invisible.

Technical Note:

The blinking-cursor options are impacted by the terminal software’s blink timeout value. For Gnome, the default timeout is ten seconds, after which the cursor will stop blinking and become steady state. To adjust this timeout value under Gnome, use either the 'dconf' editor or the 'gsettings' utility.

Get the current timeout value:
gsettings get org.gnome.desktop.interface cursor-blink-timeout
Get the range of valid values for this option:
gsettings range org.gnome.desktop.interface cursor-blink-timeout
Set a new timeout value in seconds:
gsettings set org.gnome.desktop.interface cursor-blink-timeout 25

Other desktop schemes will have a similar mechanism for adjusting the cursor blink timeout value.

Invoking - AnsiCmd Tests

Tests for the AnsiCmd library are specified as arguments to the "–ansi" command-line option.
epts --ansi=TEST_OPTION

The specific test within a group of related tests is specified by from one to four characters as detailed in this chapter. The first character indicates the test group. For instance, the letter 'C' designates the group of color-attribute tests. If a test group is invoked without indicating a specific test, then the menu of available tests in that group will be displayed and the application will exit.
epts --ansi=C   will display the color test menu:
Color Attribute Testing Options:
-----------------------------------------------
'f' Four-bit Fgnd/Bkgnd color attributes.
'b' Background color attribute options.
't' Table lookup, 8-bit color attributes.
'r' R/G/B color-attribute matrix (6x6x6).
'g' Greyscale color attributes.
'a' Aixterm Fg/Bg extensions (non-standard).
'd' Decode tracking data for attribute mods.

Similarly, if a test group and a test are specified, but the test requires an argument or arguments, then a menu of available arguments for that test will be displayed and the application will exit.
epts --ansi=Cr   will display the RGB color test arguments:
RGB Test Options:
---------------------------------------------------
'r' Red : Display full range of red colors.
'g' Green: Display full range of green colors.
'b' Blue : Display full range of blue colors.
'y' greY : Display full range of greyscale colors.
'w' Web : Display "web-safe" colors.

A few test require two(2) arguments, for example:
epts --ansi=Tec   Terminal group, Echo test, Cursor keys

If a test and its argument(s) are fully specified, then optionally, the next character indicates the text color attribute to be used for outputting the results of the test. The available color attributes are:
'k' blacK 'r' Red
'g' Green 'n' browN
'b' Blue 'm' Magenta
'c' Cyan 'y' greY
If not specified, the terminal default color is used.
Note: The color-attribute tests will ignore this argument.
Examples:
epts --ansi=Eb — Perform 'E'rasure test with 'b'lue text.
epts --ansi=Ac — Perform 'A'SCII code test with 'c'yan text.
epts --ansi=Tig — Perform 'T'erminal 'i'nput test with 'g'reen text.

Summary of Options

OPTION	DESCRIPTION
test C	Color tests
test P	Positioning tests
test E	Erasure tests
test A	Ascii control code tests
test F	Font switch test
test I	Ideograph test
test T	Terminal setup tests
test W	Window tests
test S	Sandbox

Options for testing the functionality of the AnsiCmd-class library.

For options which require arguments, the option must be immediately followed by the EQUAL sign (’=’) which must be immediately followed by its argument. If the argument string contains space characters, enclose it in quotation marks.

Please see Development and Testing or study the AnsiCmdTest.cpp source file for more information about how the individual tests are constructed.

The majority of escape sequences definined in the ECMA-48 (ANSI) standard are related to setting foreground and background color attributes. These definitions reflect the evolution of color support on hardware terminals and within terminal emulators from 3-bit (8 colors) to 4-bit (16 colors) through today’s so-called true-color (usually 24-bit) systems.

Each of the color palettes supported by the standard is exercised by one or more of the color-attribute tests listed here.

One group of the escape sequence defined by the standard provides various ways to set the cursor position. Some of these sequences set an “absolute” (terminal-relative) position. Others define a move relative to the current cursor position. All the supported variations are used during this test.

In the early days of computing, terminals were extremely slow. For this reason, several innovative ways of erasing an area of the display were implemented to increase the speed of display updates. Some of these include erasing part of a line, a whole line, and either the top half or bottom half of the display. It is even possible to “erase” the data which has already been scrolled out of the window. (It was a whole thing....don’t ask :-)

ASCII control codes (00h - 1Fh) were an important part of systems which used serial communication (e.g. Teletype machines) for user interaction. On modern systems, most of these codes are swallowed by the terminal software and never become available to the console application. A few however are vital to operation. The most common are null(00h), bell(07h), backspace(08h), horizontal-tab(09h), linefeed i.e. newline(0Ah), vertical-tab(0Bh), form-feed(0Ch), carriage-return(0Dh), and of course Escape(1Bh). Others may be used in specialized circumstances.

This test transmits each of the ASCII control codes to the terminal and reports the terminal’s response (if any).

A “font” is a set of glyphs (visible pictures) which are used to represent the “codepoints” of a character set. The ECMA-48 (ANSI) standard defines a method for selecting any of ten(10) fonts to be used for display text.

The "Primary Font" is specified in the aeSeq enumerated type as:
aesPRIMARY_FONT (decimal 10)

The "Alternate Fonts" are specified by the aeSeq value of:
aesALTERNATE_FONT
with a numeric argument between 1 and 9 (inclusive). These are translated to ANSI command codes 11 through 19, respectively.
Please see acSetFont for more information.

Testing thusfar indicates that setting alternate fonts is not supported by the terminal emulators used during development. The font is set in the terminal’s Preferences/Settings and appears to be unavailable to console applications; however, this tests exercises the font commands, and further research will be conducted.

An “ideogram” is technically a symbol representing a concept or and idea, or what today we would call a “meme”. Street signs without words, mathematical-operator symbols or a photo of a cat hanging onto a branch with one paw could be considered as ideograms.

The ideograms defined by the ECMA-48 (ANSI) standard appear to have been indended as line-drawing tools or text decorations; however, they seem to have been abandoned before they were completed. As such, they are unlikely to be supported by modern terminals; however, this test issues the associated escape sequences to see what happens i.e. nothing:
aesIDEO_UNDER // ideogram underlined
aesIDEO_UDOUBLE // ideogram double-underlined
aesIDEO_OVER // ideogram overlined
aesIDEO_ODOUBLE // ideogram double-overlined
aesIDEO_STRESS // ideogram stress marking
aesIDEO_OFF // all ideogram attributes off

This test exercises the various terminal configuration options and the internal tracking data related to those options.

The window group consists of API-level algorithms which are implemented at a higher abstraction level compared to the basic ANSI escape sequences.

At an intermediate level are the line-drawing and box objects which simply draw lines and rectangles to the display. These objects are defined by the acDrawLine method and the AC_Box Class, respectively.

At the higher level of abstraction is the ACWin Class which defines a relatively primitive dialog window which optionally contains a user-defined array of text fields (skForm Class), with more sophisticated input and output methods which may be used to display information or to interact with the user.

The “Sandbox” is a common name among nerdy types to indicate a work area in which experimental operations may be performed without compromising the platform as a whole.

Invoking the Sandbox executes user-defined functionality created for ad hoc testing. Note that code created in the Sandbox may be affected by the AnsiCmd class initialization as specified by arguments to the “--term” command-line option.
See Invoking - Terminal Setup for more information.

Invoking the Sandbox test may include one or two optional arguments which are passed as parameters to the Sandbox method. Each of these optional arguments consists of a single alpha-numeric character, (case insensitive).

Examples:
epts --ansi=S # invoke the Sandbox with no arguments
epts --ansi=St # invoke the Sandbox with one argument
epts --ansi=S4c # invoke the Sandbox with two arguments

The specified arguments will be displayed in the top row of the window as shown, and these parameters may be referenced in the usual way.
(A question mark will be displayed for unspecified argument(s)).

Invoking - EarthPoints

Summary of Options

OPTION	DESCRIPTION
coa option	Specify the first set of  global coordinates.
cob option	Specify the second set of  global coordinates.
file option	Specify a file containing  global coordinate pairs.
formula option	Specify the formula to be  used to calculate distance.
convert option	Convert coordinate-pair  format to alternate formats
color option	Specify color attribute for  reporting results.
verbose option	Display verbose output for  results of calculation.
window option	Display the report within a  window object.
dump option	Display and verify contents  of a file of GPS records.
version option	Reports EarthPoints version  number and copyright info.
help option	Display all EarthPoints and  AnsiCmd options
helpless option	Same as '--help' option  except pipe through 'less'

Options may be specified in any order.

For each option that requires one or more arguments, the option name and its argument(s) may be separated by either '=' or ' ' (space). Note that if the argument contains whitespace, then the entire argument sequence must be enclosed within single-quotes or double-quotes. This prevents the terminal’s shell program from “interpreting” (trashing) your argument formatting.

Examples:
    --coa=Miami:25.775163:80.208615
    --coa 'Miami: 25.775163 : 80.208615'
    --cob="Buenos Aires: -34 36 12.0 : -58.381666667"
    --file='Europen Capitol Cities - 2007.txt'

Note: As a convenience, the long-form options may be uniquely specified in a truncated form. At least six (6) characters of the option must be specified. This consists of the two 'dash' characters, plus the first four characters of the option name. Example: The “--verbose” option may be uniquely specified as “--verb”.

GPS Coordinate Records

A GPS coordinate record has the following format:
[LABEL:] LATITUDE : LONGITUDE
where:

• LABEL: — (optional) city or place name associated with the
  coordinates, followed by the colon character (':')
  which separates the label from the latitude field.
• LATITUDE — (required) Specify the latitude for the record
  in degrees or radians.
• colon (:) — (required) Separates latitude and longitude values.
  
• LATITUDE — (required) Specify the longitude for the record
  in degrees or radians.

Whitespace between fields of the record is optional, and will be ignored.
Whitespace within a coordinate field delimits the tokens within that field:
Examples: '25 46.50978' _or_ '25 46 30.5868'
The label field is simple text, and may contain spaces if desired. (Note the trailing colon ':').
Example: "Miami, Florida, USA:"

Latitude and longitude pairs may be expressed in either degrees or radians.
Within a latitude:longitude pair, each value may take one of the following formats.

1. a decimal degree value

     Examples:
     --coa='Miami: 25.775163 : -80.208615'
     --cob='Buenos Aires: -34.603333333 : -58.381666667'
   

   Note that positive degree values indicate North latitude or East longitude, while negative values indicate South latitude or West longitude."

2. a decimal radian value

     Examples:
     --coa='Miami: 0.449861R : 4,883281R'
     --cob='Buenos Aires: 5.679243R : 5.264233R'
   

   Note that the trailing ’R’ character of each value indicates radians. Note also that an arc in radians is expressed as a positive value only.

3. an integer degree value followed by a decimal minutes value

     Examples:
     --coa='Miami: 25 46.50978 : -80 57.948611'"
     --cob='Buenos Aires: -34 36.20 : -58 22.90'
   

4. an integer degree value followed by an integer minutes value, followed by a decimal seconds value

     Examples:
     --coa='Miami: 25 46 30.5868 : -80 57 56.91666'
     --cob='Buenos Aires: -34 36 12 : -58 22 54.0'
   

Invocation Options

Specify the record containing the first pair of GPS coordinates.

Formatting of the record is described in the GPS Coordinate Records section, above.

Two sets of GPS coordinates are needed to calculate arc length. See the "cob" option, below.

Please See verbose option, below for sample output formatting.

Specify the record containing the second pair of GPS coordinates.

Formatting of the record is described in the GPS Coordinate Records section, above.

Two sets of GPS coordinates are needed to calculate arc length. See the "coa" option, above.

Please See verbose option, below for sample output formatting.

Specify a file containing a database of GPS coordinate pairs and identify two specific records from that database. These records represent the endpoints of the arc distance to be calculated.

The target file is a plain text file containing any number of GPS records. The individual records follow the same format as command-line record specification described at the beginnig of this chapter. An example database file is shown below. (Not that you would ever do anything so foolish, but the filename may not contain the colon ’:’ character.)

Each target record is specified by its label, either the full label text, or a substring which uniquely identifies the beginning of the record label. The scan is case-insensitive. Specifying the database filename and record labels takes the form:
--file='FILENAME:LABEL_A:LABEL_B'

The following record specifications are equivalent.
epts --file='GPS_Records.txt:Chicago, IL:Miami, FL'
epts --file='GPS_Records.txt:chi:Mia'

Alternatively, the records may be specified using the index of of the record(s) within the database using the special token: “LABn” where 'n' is a zero-based index.

Examples:
epts --file='GPS_Records.txt:Chicago, IL:LAB14'
epts --file='GPS_Records.txt:LAB2:Miami, FL'
epts --file='GPS_Records.txt:LAB2:LAB16'

Example GPS Record Database

Each record lives on a seperate line. Note the range of available coordinate formats. Blank lines and lines beginning with the hash character (’#’), are interpreted as comments and will be ignored.

# ---------------------------------------------------
# The Not Fully United Kingdom.
# ---------------------------------------------------
#                                              INDEX
#                                              -----
# London, England                                0
London         : 51 30 26.0 : -0 7 39.0

# Edinburgh, Scotland                            1
Edinburgh      : 55.953056 : -3.188889

# Cardiff, Wales                                 2
Cardiff        : 0.898525R : 3.086106R

# Belfast, Northern Ireland                      3
Belfast        : 54.596521 : -5.930578

Three GPS database files are included with the AnsiCmd package:
US_Capitols.txt, UK_GPS.txt and testpoints.txt.

Select the formula to be used for calculation of the arc distance between the two specified GPS coordinates.
(Three(3) characters are sufficient to uniquely identify the argument.)

Available formulae:

lambert The Lambert formula calculates the arc on an ellipsoid. haversine The Haversine formula calculates the arc on a sphere. all Displays the calculations for all supported formulae. Examples: epts --coa='36.1:-14.3' --cob='37.7:-12.4' --form=lambert (default) epts --coa='36.1:-14.3' --cob='37.7:-12.4' --form=haversine epts --coa='36.1:-14.3' --cob='37.7:-12.4' --form=all

Additional formulae may be implemented in a future release.

Convert one(1) latitude or longitude value from the given format to the alternate supported formats and display the results.

The 'convert' option takes one argument of the form:
--convert=GPS_COORDINATE_VALUE

This option is useful primarily for debugging the input-parsing routines; however, it may also be useful for experimenting with the various GPS coordinate value formats.

Example coordinate values and the report generated:

epts --convert='-80 57 56.91666' Converted Value: dec:-80.965810 decimal degrees (degrees+minutes+seconds) deg:-80.000000 degrees component min: 57.000000 minutes component sec: 56.916660 seconds component rad: 1.728473 radians fmt: vfSec source format identifier (enum valFmt) epts --convert=4.2579R Converted Value: dec:-63.959700 deg:-63.000000 min: 57.000000 sec: 34.918520 rad: 4.257900 fmt: vfRad

Specify the foreground and background color attributes for display of the output. The terminal window’s color attributes are used by default.

If the --window option is used, then the window’s border attributes may also be specified. (Border attributes, if specified, are ignored for TTY output.)

The '--color' option may be used to specify alternate attributes. The format of the arguments takes the form:
--color=text_fgnd:text_bkgnd[:border_fgnd:border_bkgnd]

Each color is specified as one of the following:

'black' 'blue' 'red' 'magenta' 'green' 'cyan' 'brown' 'grey' 'dflt' use terminal default attribute (The first four characters of the name uniquely identify the color.) Examples: epts --color=blue:grey // blue text on grey background epts --color=green:dflt // green text on default background epts --color=dflt:blue // default text color on blue background // blue text, grey bkgnd, cyan border fgnd, black border bkgnd epts --color=blue:grey:cyan:black // default text fgnd:bkgnd, magenta border fgnd, blue border bkgnd epts --color=dflt:dflt:magenta:blue

The standard arc-distance report displays the coordinates in both degrees and radians, and then displays the arc-distance in both kilometers and miles, calculated using the specified formula.

The verbose arc-distance report displays the same information, except that the coordinate values in degrees are broken down into their component parts: Degrees, Minutes and Seconds.

Standard Report:

Miami, FL                         Buenos Aires, AR
======================            ======================
LATITUDE    LONGITUDE             LATITUDE   LONGITUDE
----------  ----------            ----------  ----------
  0.44986     1.74169  Radians      2.53765     2.12264
 25.77516   -80.20862  Degrees    -34.60333   -58.38167

Distance: 12905.069560 km (8018.838378 mi)

Verbose Report:

Miami, FL                         Buenos Aires, AR
======================            ======================
LATITUDE    LONGITUDE             LATITUDE   LONGITUDE
----------  ----------            ----------  ----------
  0.44986     1.74169  Radians      2.53765     2.12264
 25.77516   -80.20862  Degrees    -34.60333   -58.38167
       25         -80  Deg(int)         -34         -58
       46          12  Minutes           36          22
       31          31  Seconds           12          54

Distance: 12905.069560 km (8018.838378 mi)

By default, the arc-distance report is displayed in the terminal window using common TTY (Teletype) style output. This output is formatted using basic ANSI escape sequences.

Optionally, the arc-distance report may be formatted within an ACWin-class window object positioned within the terminal window. The ACWin class is derived from the base AnsiCmd class and implements more advanced ANSI formatting. It is designed to resemble an 'ncurses' dialog window. Please See ACWin Class for more information.

By default, the dialog window is positioned with the origin (upper-left corner) at row one(1), column four(4) of the terminal window. However, any position within the terminal window may be specified using parameters of the form: 'row:column'.

The row and column are 1-based offsets from the upper-left corner of the terminal window. See cursor offsets for a discussion of 1-based versus 0-based terminal offsets.

Additionally, specifying a zero (0) value for either parameter indicates that the dialog is to be centered in that dimension. See examples below.

If the specified position would place any part of the dialog beyond the boundaries of the terminal window, then the position will be automatically adjusted to ensure that the entire dialog is visible.

Examples:
epts --window // no position specified, use default 1:4
epts --window=2:1 // positioned at row 2, column 1
epts --window=12:0 // positioned at row 12, centered horizontally
epts --window=0:5 // centered vertically, and at column 5
epts --window=0:0 // centered both vertically and horizontally
In the following example, the row specified is beyond the number of rows in the terminal window, so the vertical offset will be automagically adjusted such that the lower edge of the dialog is on the bottom row of the terminal window:
epts --window=99:0 // auto-adjusted row, and centered horizontally

┌─┤ EarthPoints v:0.0.03 (c) 2022-2023 The Software Samurai ├─┐ │ Miami, FL Buenos Aires, AR │ │ ====================== ====================== │ │ LATITUDE LONGITUDE LATITUDE LONGITUDE │ │ ---------- ---------- ---------- ---------- │ │ 0.44986 1.74169 Radians 2.53765 2.12264 │ │ 25.77516 -80.20862 Degrees -34.60333 -58.38167 │ │ Distance: 12905.069560 km (8018.838378 mi) │ │ │ │ Press Any Key To Exit... │ └──────────────────────────────────────────────────────────────┘

Please visit the author’s website to download the NcDialog API, and for a discussion of full-featured dialog windows based on the ncurses library. See By the Same Author for details.

Display and verify the formatting of GPS coordinate records contained in the specified file.

A database of GPS coordinate records is a plain text file with a series of records in the form:
Phoenix, AZ : 33 26 53.15 : -112 5 49.54
consisting of three(3) fields, seperated by colons (’:’).
Label : Latitude : Longitude

Formatting of the record is described in the GPS Coordinate Records section, above.

When constructing a database of GPS coordinate records, the syntax of the records should be verified.
The syntax of each record in the database is verified using the "--dump" option.

Example:
epts --dump='US Capitols.txt'

The following is the output for the scan of the 'testpoints.txt' file included in this package.

EarthPoints (epts) v:0.0.03 Copyright(c) 2022-2023  The Software Samurai
========================================================================
Validate contents of GPS record file: 'testpoints.txt'
------------------------------------------------------
00) :25 46 30.5868 : -80.208615                             (OK)
01) Miami, FL : 25 46 30.5868 : -80.208615                  (OK)
02) Buenos Aires, AR : -34 36 12.0:-58 22.90                (OK)
03) Indianapolis, IN : 39.768611 : -86.158056               (OK)
04) Lafayette, IN : 40.417222 : -86.878611                  (OK)
05) San Francisco, CA : 37.7775 : -122.416389               (OK)
End-Of-File

If a syntax error is found, it will be indicated by a status of “(?)”.
For example, this record is missing the madatory field delimiter ':' between the Label and Latitude fields.
01) Miami, FL 25 46 30.5868 : -80.208615 (?)

Command-line Help. Display a brief summary of command-line usage and options. (overrides everything on command line except '--version')

   EXAMPLES:  epts --help
              epts -h

Display command-line help. Same as the '--help' option above except that the help menu will be piped through the 'less' utility.

   EXAMPLES:  epts --helpless
              epts -hl

Display the EarthPoints version number and copyright information.
(overrides everything else on the command line)

To also report the AnsiCmd-class version number, append an 'a' to the argument.

   EXAMPLES:  epts --version
              epts --versionA

Introductory Notes

For those who are new to the terminal (emulator) environment, or for those who are interested in the technical details of terminal configuration, this chapter provides an overview of the challenges the author faced during development of this project, and our responses to those challenges.

Terminal Environment

A common saying in Linux is that “Everything is a file.” While it is true in general that most things are acessed as if they were files, many of the underlying targets are not actually files on the storage media. This is nowhere more apparent than with the input and output data streams of the terminal emulator. Generically, these are known as Standard Input(stdin), Standard Output(stdout) and Standard Error(stderr).

Within the AnsiCmd library, these are referred to by their so-called file handles which are named by the 'TermStream' enumerated type:

These streams are not actual files, but the terminal’s VIRTUAL configuration files. Therefore, practically speaking, when modifying terminal settings, it doesn’t matter whether the stdIn, stdOut or stdErr stream is referenced because they are not actual file descriptors. Instead, they reference the underlying terminal-attributes structure.
For more information, see Terminal Configuration.

ANSI Escape Sequences

ANSI (American National Standards Institute) escape sequences are simply a well-defined set of byte sequences that may be used to communicate with the host terminal. They are hopelessly old-fashioned, slow, unreliable, difficut to use and all-around relics from the mid-20th century. That being said, they are also widely supported and a lot of fun to play with.

ANSI escape sequences include functionality for cursor positioning, erasing blocks of text, setting color attributes and text modifiers such as bold, italic etc., and all other attributes defined by the ECMA-48, ANSI X3.64 standard. See also ISO/IEC 6429, FIPS 86, ISO/IEC 2022, JIS X 0211.

Wikipedia:   https://en.wikipedia.org/wiki/ANSI_escape_code

Escape-sequence Definitions

Within the AnsiCmd library, the individual ANSI escape sequences are referenced by the “enum aeSeq” enumerated type.

aeSeq (ANSI Escape Sequence) is located in the AnsiCmdDef.hpp header file and includes all the ANSI escape sequences defined by the ECMA-48, ISO/IEC-6429 standard.

Note that each member begins with “aes” to indicate that it belongs specifically to this enumerated type. The short example below should give the basic idea of how aeSeq is constructed.

enum aeSeq : short
{
   //** Text Modification Options. **
   aesRESET = 0,              // reset all attributes
   aesBOLD,                   // bold (increase intensity)
   aesFAINT,                  // faint/dim (decrease intensity)
   aesITALIC,                 // italic (or inverse)
   . . .
   //** Foreground Color Attributes (3-bit and 4-bit color selection) **
   aesFG_BLACK,               // set foreground color to black (i==24)
   aesFG_RED,                 // set foreground color to red
   aesFG_GREEN,               // set foreground color to green
   . . .
   //** Background Color Attributes (3-bit and 4-bit color selection) **
   aesBG_BLACK,               // set background color to black (i==41)
   aesBG_RED,                 // set background color to red
   aesBG_GREEN,               // set background color to green
   . . .
   //** Indexed Color Attribute Options (8-bit color and greyscale) **
   aesFG_INDEX,               // set foreground color by lookup table index (0-255)
   aesBG_INDEX,               // set background color by lookup table index (0-255)

   //** Red/Green/Blue Color Attribute Options (24-bit color) **
   aesFG_RGB,                 // set foreground color by r/g/b register number
   aesBG_RGB,                 // set background color by r/g/b register number

   //* Cursor-positioning Options *
   aesCUR_HOME,               // set cursor at 1,1
   aesCUR_ABSPOS,             // set (absolute) cursor at specified row;column position
   aesCUR_ROWSUP,             // move cursor upward by specified number of rows
   . . .
   //* Text Erasure Options *
   aesERASE_BOW,              // erase from cursor to bottom of window
   aesERASE_TOW,              // erase from cursor to top of window
   aesERASE_WIN,              // erase entire window ('clear')
   . . .
   //* Alternate Font group *
   aesPRIMARY_FONT,           // primary font      (font 0)
   aesALTERNATE_FONT,         // alternate fonts (font 1 through font 9)

   //* ASCII Control Codes. *
   aesBELL,                   // '\a' terminal "bell" (beep, ping, etc.)
   aesBKSP,                   // '\b' backspace
   aesHTAB,                   // '\t' horizontal tab
   . . .
   //* Ideogram (logogram) group of options *
   aesIDEO_UNDER,             // ideogram underlined
   aesIDEO_UDOUBLE,           // ideogram double-underlined
   aesIDEO_OVER,              // ideogram overlined
   . . .
   //** Aixterm codes are not part of the    **
   //** ANSI standard, but may be supported. **
   aesAIXFGb_BLACK,           // set foreground color to bright black (grey)
   aesAIXFGb_RED,             // set foreground color to bright red
   aesAIXFGb_GREEN,           // set foreground color to bright green
   . . .
   aesCOUNT                   // number of items in enumerated type list
} ;   // enum aeSeq

The members of aeSeq index the corresponding byte sequences which are private data located in the AnsiCmd.cpp source module.
static const wchar_t *ansiSeq[aesCOUNT];

A majority of the element of this array are constant byte sequences; however, the sequences which require parameters are defined as formatting templates as shown in these examples.

Constant byte sequence:
L"\x1B[22;31m" // aesFG_RED
Formatting template:
L"\x1B[38;5;%hhum" // aesFG_INDEX

Note that these sequences are defined as wide character strings because as explained elsewhere (Terminal Configuration), 8-bit character streams are so very 1970s.

Multi-threading

ANSI escape sequences should not be used in multi-threaded applications due to timing issues and resource conflicts. For multi-threaded applications, the author recommends our NcDialog API, which is a fully thread-safe ncurses-based library for creating formatted-text console applications.

One practical effect of avoiding multi-threading is in the area of library functions which handle timing and delays.

In C++, the accepted way to delay the action is to use the ’chrono’ class to define the delay, and the ’sleep_for’ method to execute it. However, ANSI escape sequences are inherently incompatible with a multi-threaded environment. For this reason, the AnsiCmd class uses the C-language nanosleep() function. This function is technically sophisticated, but clunky in implementation; so please refer to our iplementation of nanosleep(): nsleep() for details. (see nsleep)

Terminal Configuration

Initial terminal configuration is specified by passing an initialized TermConfig object to the AnsiCmd constructor.
   See TermConfig Class.

Subsequent modifications to the terminal environment are specified by calling the associated AnsiCmd-class method(s).
   See AnsiCmd Class Methods.

The actual configuration commands are issued by the TermSet object, which is a private member of the AnsiCmd class as described below.
   See TermSet Class.

TermConfig Class

Initialization of the TermConfig object may be done directly by the application when invoking the AnsiCmd constructor:
   AnsiCmd constructor,
or may be performed by the user through command-line options:
   Invoking - Terminal Setup.
The options provided by the user are validated and stored in the data members of the TermConfig object.

      Data Members

• TermStream termStream
  Specify the target I/O stream as a member of enum TermStream:
     stdIn (stdin), stdOut (stdout), stdErr (stderr)

  Note: In practical terms, the selection of the target stream is not important because changes made to one stream are reflected in all streams. Internally, 'stdIn' is used when not specified otherwise.

• char configFile[gsMAXBYTES]
  NOT YET IMPLEMENTED
  Name of configuration file (default “ansicmd.cfg”) which specifies all terminal configuration options.
• char localeName[LOCALE_LEN]
  Filename of alternate locale (null string by default). If not specified, locale will be taken from terminal environment.

  For those not familiar with the purpose of the 'locale' specification, the locale selected controls how characters are encoded, formatting of numbers, timestamps and currency, interpretation of punctuation, comparisons of text strings and other text formatting decisions. By default, applications start in the so-called “C-locale” which is not really a locale, but a lack of locale which interprets everything in terms of ASCII and English, rendering the application basically useless. For this reason, it is strongly recommended that all application set the locale for the language, character set and text conventions in use by the target system.

• EchoOpt echoOption
  The selected Echo Option specifies how the data input stream is to be managed.

  Characters received through 'stdin' will be echoed (displayed) in the terminal window according to the specified member of enum EchoOpt.

  When system buffering of input is active, the application has no direct control over input echo, so this option will be ignored. However, when input buffering is disabled (see the 'bufferInput' variable, below), the specified echo option will be used:
  

  • noEcho : input data are not echoed to the display.
  • termEcho: terminal automatically echoes input
    The terminal always controls input echo when input buffering is enabled, and may be allowed to control input echo when buffering is disabled.
  • softEcho[A|C|D|E]: the 'acRead' input methods echo (display) all graphing (printing) characters to the terminal window as they arrive. The “special” keys (cursor movement, backspace, delete, insert) are processed according to specified soft-echo sub-option.
    
    • softEchoA - All special keys are captured, decoded and available to the application.
      
    • softEchoC - Cursor keys only: UpArrow, DownArrow, LeftArrow, RightArrow, Home, End, PageUp, PageDown, Tab and Shift+Tab. (Edit keycodes are excluded.)
      
    • softEchoD - Disable (capture and discard) all special keycodes.
      
    • softEchoE - Edit keys Backspace, Delete and Insert, plus Tab and Shift+Tab. (Cursor movement keycodes are discarded.)

    The keycodes in each special-key group may be adjusted, as we receive more feedback from users about how they uses these options.

    Please see Soft Echo Options below for more information.

• bool bufferInput
  Specify whether data from 'stdin' will be buffered by the system or whether it will be sent directly to the application as soon as it arrives in the input stream.
  'false' : disable input buffering
  'true; : input buffering enabled (default)
  Note that both the soft-echo options (described above) and non-blocking read of the input stream require that input buffering be disabled.
• bool wideStream
  Select the character width of the input/output streams.
  'true' : wide (32-bit) I/O streams, wcin and wcout
  'false' : narrow (87-bit) I/O streams, cin and cout
  Please see acSetStreamWidth for additional information.
• bool nonStandard
  Specify whether the host terminal is ANSI compliant.
  A compliant terminal supports all of the common commands of ANSI standard (ANSI X3.64 (ISO/IEC6429)). 'true' : non-standard terminal emulator
  'false' : ANSI compliant terminal emulator (default)
  The three terminal emulators used during development, Gnometerm, Konsole and XTerm are all fully compliant with the standard. To determine whether your preferred terminal supports all the ANSI escape sequences defined by the standard, run the full set of tests provided with this library. Please see Development and Testing for full information.
• CCH_Type bcType
  Capture the Panic Button (CTRL+C key). The signal-capture type is specified as a member of enum CCH_Type:
  
  • cchtTerm   - Terminal handles CTRL+C break-signal.
  • cchtExit   - The application terminates execution in an orderly way.
  • cchtUser   - Ask user whether to exit or discard the signal.
  • cchtIgnore - Ignore (discard) the break signal.

  See Capturing the Break Signal, below for more information.

• bool bcAlert
  For 'bcType' == cchtIgnore ONLY: Specify whether the application should sound an audible alert when the break signal is captured and discarded. (This is a polite way of telling the user to stop pressing the Panic Button.)
  'true' : sound the alert when break is captured and discarded
  'false': silently discard the captured break signal
• CurStyle cursorStyle
  Select cursor style. The cursor style is specified as a member of enum CurStyle:
  
  • csDflt    Terminal default cursor style.
  • csBblock The shape of the cursor is a full-character cell, blinking block. (This is also generally the terminal default shape.)
  • csSblock The shape of the cursor is a full-character cell, steady (non-blinking) block.
  • csBuline The shape of the cursor is a blinking underline i.e. one or two pixel rows at the bottom of the character cell.
  • csSuline The shape of the cursor is a steady underline i.e. one or two pixel rows at the bottom of the character cell.
  • csBvbar   The shape of the cursor is a blinking vertical bar i.e. one or two pixel columns at the left edge of the character cell.
  • csSvbar   The shape of the cursor is a steady vertical bar i.e. one or two pixel columns at the left edge of the character cell.
  • csHide    Hide the cursor i.e. make it invisible. Note that the previouly selected cursor shape will be retained.
  • csShow    Show the cursor i.e. make it visible.
• aeSeq foreground
  Specify the initial foreground (text) color attribute.
  This is a member of the 4-bit foreground color group within enum aeSeq: aesFG_xxxx (default:aesFG_DFLT)
  Please see ANSI Escape Sequences for examples.
• aeSeq background
  This is a member of the 4-bit foreground color group within enum aeSeq: aesBG_xxxx (default:aesBG_DFLT)
  Please see ANSI Escape Sequences for examples.

Capturing the Break Signal (CTRL+C)

The break signal is generated by the user pressing the Control+C key combination. By default, the break signal is captured by the terminal which then sends the kill signal to the application running within the terminal window. It is often useful, however, to redirect the break signal to application control. The AnsiCmd library can perform this redirection in either of two ways.

1. Activate the break-signal handler during instantiation of the AnsiCmd class by setting the 'bcType' member of The TermConfig object which is passed as the argument to the AnsiCmd constructor.
   Please see TermConfig Class and Invoking - Terminal Setup for detailed instructions on specifying a break-signal handler using this method.
2. Specify redirection of the break signal to application control through a call to the acCaptureBreakSignal method.

   While the first option always invokes the AnsiCmd library’s default handler, the 'acCaptureBreakSignal' call can specify either the default handler or an alternate handler provided by the application.

   The 'acCaptureBreakSignal' method can also be used to return control to the terminal’s signal handler.

The mechanics of transferring control of the break signal to the application are straightforward, but non-trivial. It is accomplished by “registering” a signal-handler function with the system using the C-library function:
'signal( int SIGNUM, sighandler_t ACTION )'.
This function is defined in the 'signal.h' header file.
The SIGNUM parameter in this case is the macro 'SIGINT' (the interrupt signal). The ACTION parameter is the address (name) of the function to which the break signal will be directed.

The terminal’s signal handler is defined by the macro 'SIG_DFL', while the application’s handler may be specified by the name of any (non-member) function in the application which is configured to process the signal.

The non-member function in the AnsiCmd library is cryptically named 'BreakSignal_Handler'. The system call is then:
signal ( SIGINT, BreakSignal_Handler );

Because we want to provide for potential user interaction when the break signal is received, we perform the slightly dangerous operation of allowing the non-member function to call a private AnsiCmd-class member method:
breaksignalReceived ( int sigNum );
This is where the action takes place.

The type of operation to perform has been specified during handler setup, and is a member of enum CCH_Type (Control_C_Handler Type).

• cchtTerm - Terminal handles CTRL+C break-signal by issuing the kill signal to the application running within the terminal. Generally, this can be done without serious consequences; however, it may be necessary to manually reset the terminal by calling the 'reset' utility to return the terminal configuration to a known state. For instance, if the application is terminated using CTRL+C, the current terminal attributes will still be active when the terminal shell regains control.
• cchtExit - The application will perform any specified housekeeping tasks, and then immediately terminate execution, returning control to the terminal shell program. For the AnsiCmd class, “housekeeping tasks” include returning the terminal configuration to its original state, deleting all allocated objects by calling the destructors for the objects in the proper order, setting the exit code and executing the C-library exit sequence.
• cchtUser - Prompt user for whether to exit the application or to discard the break signal and continue execution.
     Break Detected. Exit? (N / y): _   
  This message is written to the upper-right corner of the terminal window and uses a blinking text attribute to draw the user’s attention.
• cchtIgnore - Ignore (discard) the break signal and continue execution of the application; optionally, sounding an audible alert so the user knows that the signal was received, but discarded. (see bcAlert member of the TermConfig class for enabling the audible alert.)

Soft Echo Options

“Soft Echo” options define a range of ways in which keyboard input can be captured and filtered before it is echoed (written) to the terminal window.

The primary method for selecting the the soft-echo option is to specify it during a call to the acBufferedInput method which disables input buffering and optionally specifys the character-echo option and whether the input stream uses a blocking or non-blocking read.

The soft-echo option may also be specified as a command-line option. See the 'echoOption' member in the discussion of the
TermConfig Class, above.

If the echo option is termEcho, then the terminal decides what input is echoed to the display. If the echo option is noEcho, then keyboard input is not written to the display.

Specifying one of the soft-echo options disables automatic echo of keyboard input to the display, and then sorts the incomming keycodes into two main groups: graphing (printing) characters and non-printing control codes.

Graphing (printing) characters are written to the display in the usual way, but control codes are captured, and either converted to one of the “special” keys or discarded according to the selected soft-echo option.

• softEchoA - All special keys are captured, decoded and available to the application, which can then interpret the keycode or discard it.
  This is the default soft-echo option.
• softEchoC - Cursor keys only: UpArrow, DownArrow, LeftArrow, RightArrow, Home, End, PageUp, PageDown, Tab and Shift+Tab.
  (Edit keycodes are excluded.)
  
• softEchoD - Disable (capture and discard) all special keycodes.
  
• softEchoE - Edit keys Backspace, Delete, Insert, AltEnter, plus Tab and Shift+Tab. (Cursor movement keycodes are discarded.)

See the next section for more information on the “ special” keycodes.

Decoding the “Special” Keys

The “special” keycodes consist of certain keycodes which are presented to a console application in the form of escape sequences. Many keyboard keys are encoded in this way: the Function Keys, the Cursor Positioning keys, the Backspace/Delete/Insert keys, and most of the keycodes generated in combination with the so-called conditioning keys: Shift, Control, Alt.

For a (nearly) complete list of keystrokes that generate escape sequences and the sequences they generate, please download the author’s NcDialog API package and study the source files NCursesKeyDef.hpp and NCursesKeyDef_auto.hpp.

For the AnsiCmd library, only a small subset of these escape sequences are captured and decoded. These include:

Key Function	Esc Seq (hex)	Key Name	Glyph/Keycode
Up Arrow	1B 5B 41	wcsUARROW	↑ 2091h
Down Arrow	1B 5B 42	wcsDARROW	↓ 2093h
Right Arrow	1B 5B 43	wcsRARROW	→ 2192h
Left Arrow	1B 5B 44	wcsLARROW	← 2190h
Home Key	1B 5B 48	wcsHOME	↖ 2196h
End Key	1B 5B 46	wcsEND	↘ 2198h
Page Up	1B 5B 35 7E	wcsPGUP	↗ 2197h
Page Down	1B 5B 36 7E	wcsPGDN	↙ 2199h
Tab	09	wcsTAB	↱ 211Bh
Shift+Tab	1B 5B 5A	wcsSTAB	↲ 21B2h
Backspace	7F	wcsBKSP	↰ 21B0h
Delete	1B 5B 33 7E	wcsDELETE	↳ 21B3h
Insert	1B 5B 32 7E	wcsINSERT	↥ 21A5h
Alt+Enter	1B 0A	wcsAENTER	↧ 21A7h

   Note: Encoding of Backspace and Delete keys are specified in terminal settings.

The Copy/Cut/Paste keys (Ctrl+C, Ctrl+X, Ctrl+V) will be integrated into this group for a future release. Until then, the terminal equivalents, in concert with the system mouse, may be used: Ctrl+Shift+C, CtrL+Shift+V.

Taken together, these keycodes comprise all the standard keycodes used to edit text within an individual field or on a form consisting of multiple fields.
Please see skForm Class for a description of how these keycodes are interpreted within a form or a field.

TermSet Class

The TermSet class encapsulates the low-level access to terminal-configuration options. The AnsiCmd class methods calls the private TermSet object ('tset' member) for configuration options such as input buffering, input-echo options, cursor style, blocking vs. non-blocking input, flushing the I/O buffers and capture of the break signal (CTRL+C).

All methods and data members of the TermSet class are private, and are accessed only by the AnsiCmd (or ACWin) class. This ensures that there is only one point of access to the terminal configuration in order to avoid unfortunate configuration conflicts.

Although the functionality discussed here is not directly available to the application, it is interesting and educational to understand what is going on under the floorboards, so-to-speak.

The application may request a copy of the current terminal settings to verify that the terminal is configured as desired. The data consist of the bitfields defined in the C-language termios structure.
See acGetTermInfo for details.

      Data Members

• TermIos strOrig
  This is a copy of the I/O stream setting captured during application startup, when the AnsiCmd/TermSet classes are first instantiated.

  This data set is used to return the terminal settings to their original values when the application exits, i.e when the AnsiCmd/TermSet destructors are called.

  Please see AnsiCmd constructor for additional information.

• TermIos strMods
  This member contains data for the current terminal configuration. It is updated whenever the configuration is modified.
  
  
• TermStream aStr
  This is the (virtual) file handle for the “active” (most recently modified) I/O stream. it is a member of enum TermStream, consisting of stdIn (stdin), stdOut (stdout) and stdErr (stdErr).
  Note that stdErr is not referenced within the AnsiCmd/TermSet code, but is included for completeness.

  As noted elsewhere (see Introductory Notes), this has little practical value as a file handle because it references a virtual file which manages all three streams as a unit.

• CurStyle curStyle
  The cursor style currently applied to the visible cursor. This is a member of enum CurStyle.

  Please See S option for specifying the cursor style as a command line option, and the TermConfig Class for a detailed description of cursor styles.

• CCH_Type cchType
  This is a member of enum CCH_Type and specifies the type of Control_C_Handler (break signal handler) currently in use.

  Please See Capturing the Break Signal for a discussion of the break-signal handlers built into the AnsiCmd library.

• EchoOpt inpEch
  This is a member of enum EchoOpt and specifies whether and how keyboard input is echoed (displayed) in the terminal window.

  Please See Soft Echo Options and TermConfig Class for a discussion of input-echo options.

• bool inpBuf
  This flag indicates whether input buffering is currently enabled.
  true == buffering enabled
  false == buffering disabled

  Please See B option for specifying the input buffering option as a command line option, and the TermConfig Class for a description of input buffering. See also, the acBufferedInput method.

• bool inpBlk
  This flag indicates whether blocking read is active for the input stream.

  The term “blocking read” refers to whether the execution thread should go to sleep while waiting for keyboard input.

  By default, blocking read is active, meaning that when the application requests keyboard input from the user (see acRead), the execution thread goes into a hibernation state until the terminal signals that input is available in the buffer.

  When blocking read is disabled, a request for user input will return the first keycode in the buffer, or will immediately return a "WEOF" (zero) if no data are available in the input buffer.

  The AnsiCmd library uses non-blocking read primarily for receiving escape sequences from the terminal program and for flushing the input buffer. The acBlockingInput method makes non-blocking input available in case the application needs similar functionality.
  NOTE: This functionality can be dangerous, so use it wisely.

• bool cchAlert
  This flag indicates whether an audible “beep” is enabled to alert the user when the break signal (CTRL+C) has been received.

  Please See Capturing the Break Signal, and also the acCaptureBreakSignal method for a discussion of the break-signal handlers.

• bool strCap
  This flag indicates whether the 'strOrig' member (see above) has been initialized.
  true == member initialized
  false == member not initialized
• bool inpMod
  This flag indicates whether the 'strMods' member (see above) has been initialized.
  true == member initialized
  false == member not initialized

For additional information on terminal configuration please refer to the documentation for the C-library functions: tcgetattr, fcntl, signal and the termios structure and related macro definitions defined in termios.h and unistd.h

AnsiCmd Class Methods

• Table of Public Methods
• Configuration Methods
• Color Attributes
• Text Modifiers
• Cursor Positioning
• Input Methods
• Output Methods
• Text Erase
• Misc Methods
• API Methods
• Development Support
• Coding Example

AnsiCmd (enum acAttr) color-attribute bit fields:
0x000000FF  index for foreground color
            ......00-......0F  16  4-bit color attributes
            ......10-......E7  216 8-bit color attributes
            ......E8-......FF  24  greyscale color attributes
            ......00-......FC  232 RGB color attributes
0x0000FF00  index for background color
            ....00..-....0F..  16  4-bit color attributes
            ....10..-....E7..  216 8-bit color attributes
            ....E8..-....FF..  24  greyscale color attributes
            ....00..-....FC..  232 RGB color attributes
0x00FF0000  text modifier flags
            ..00....   plain text (no modifiers)
            ..01....   bold (intense)
            ..02....   italic
            ..04....   underline
            ..08....   overline
            ..10....   x-out (strike-through)
            ..20....   blink
            ..40....   concealed (invisible)
            ..80....   reversed fg/bg
0xFF000000  additional flags
            01......   clear existing modifiers before setting the new ones
            02......   use terminal default foreground attribute
                       (foreground index ignored)
            04......   if set, it indicates that foreground index is the
                       index of a "web-safe" RGB foreground color attribute
                       with a range of: minRGB <= value <= maxRGB
            08......   use terminal default background attribute
                       (background index ignored)
            10......   if set, it indicates that background index is the
                       index of a "web-safe" RGB background color attribute
                       with a range of: minRGB <= value <= maxRGB
            20......   (reserved)
            40......   (reserved)
            80......   (reserved as internal placeholder value)

The following shows some examples of how the bitfield is constructed.
The contruction is performed by creating a logical OR of enum acAttr members;
or in the case of 8-bit and RGB color attributes by using the 'compose' method
described above.
See also the AnsiCmd 'acComposeAttributes' public method.

To specify the terminal default foreground attribute, set the acaFG_DFLT flag.
The foreground index value will be ignored.
   Fgnd:  xxxx-x01x-xxxx-xxxx-xxxx-xxxx-....-....

To specify the terminal default background attribute, set the acaBG_DFLT flag. 
The background index value will be ignored.
   Bgnd:  xxx0-1xxx-xxxx-xxxx-....-....-xxxx-xxxx

To specify a 4-bit foreground attribute, _reset_ the acaFG_DFLT and
acaFG_RGB flags and insert the desired member of enum acAttr in the range:
acaFG_BLACK through acaFGb_GREY inclusive.

To specify a 4-bit background attribute, _reset_ the acaBG_DFLT and
acaBG_RGB flags and insert the desired member of enum acAttr in the range:
acaBG_BLACK through acaBGb_GREY inclusive.

To specify an 8-bit indexed color foreground attribute, initialize the
foreground index and _reset_ both the acaFG_DFLT and acaFG_RGB flags.
   Fgnd:  xxxx-x00x-xxxx-xxxx-xxxx-xxxx-nnnn-nnnn

To specify an 8-bit indexed color background attribute, initialize the
background index and _reset_ both the acaBG_DFLT and acaBG_RGB flags.
   Bgnd:  xxx0-0xxx-xxxx-xxxx-nnnn-nnnn-xxxx-xxxx

To specify one of the "web-safe" RGB register combinations, initialize
the foreground or background index and set the acaFG_RGB or acaBG_RGB 
flag, respectively. 
   Fgnd:  xxxx-x10x-xxxx-xxxx-xxxx-xxxx-nnnn-nnnn
   Bgnd:  xxx1-0xxx-xxxx-xxxx-nnnn-nnnn-xxxx-xxxx

To set one or more text modifiers, _reset_ the acaCLEAR_MODS flag and
create a logical OR of the desired attributes. (include existing fg/bg bits.)
Ex: acAttr fgbg = acAttr(acaFG_BLUE | acaBGb_RED);
    acAttr((fgbg |acaBOLD | acaITALIC | acaUNDERLINE) & ~acaCLEAR_MODS)
   Mods:  xxxx-xxx0-xxxx-x111-xxxx-xxxx-xxxx-xxxx

To reset one or more text modifier, set the acaCLEAR_MODS flag and _set_
the flag(s) for the modfier(s) to be reset. (include existing fg/bg bits.)
Ex: acAttr(fgbg | acaITALIC | acaCLEAR_MODS)
   Mods:  xxxx-xxx1-0000-0010-xxxx-xxxx-xxxx-xxxx

Introduction to gString

Introduction to a Wider World

Modern applications must be designed for a worldwide audience, and for this reason, the application designer must plan for multi-language support.

Fortunately, the Universal Character Set standard ISO/IEC 10646 and UTF-8, the most popular and flexible method of character-encoding smoothly provide all the character sets, alphabets and special characters which are currently in general use.

Unfortunately, the C and C++ languages offer only minimal support for internationalization. std::string and std::wstring are nothing more than a cruel joke to a serious application designer. The GTK+ toolkit’s Glib::ustring class is an excellent internationalization tool, but it requires installation of the GTK+ toolkit’s ’glib’ and ’glibmm’ libraries. For more information on Glib::ustring, see:
http://library.gnome.org/devel/glibmm/unstable/classGlib_1_1ustring.html

’gString’ falls halfway between the full feature set of Glib::ustring and the meaningless garbage that is std::string. ’gString’ consists of one C++ header file and one C++ source code module. ’gString’ is integrated into the NcDialog API library, but may also be compiled independently as a small (16Kb) link library or the source may be embedded directly into your application.

Preparing to Support Multiple Languages

Here are the basic ideas you will need to understand in order for your application to smoothly support multiple languages.

1. ASCII (American Standard Code for Information Interchange) is only the very first step in character encoding. It is an ancient and venerable encoding, but supports only the 95 printable characters of the basic Latin alphabet.
   If you think you can say "你是在欺骗自己！" in ASCII, you’re just deluding yourself!
2. NEVER assume that one character can be represented with one byte.
3. NEVER assume that one character is one display column in width.
4. The idea that text flows from left-to-right, may only be PROVISIONALLY assumed, because again: "!איר זענט נאָר דילודינג זיך" you’re just deluding yourself.
5. NEVER assume that "everyone reads English, so why bother?". Native speakers of Spanish, French, Chinese, the various flavors of Arabic and others (i.e. your potential customers) all have a significant impact on the daily events of our planet, so include them when planning for your next killer app.

See also a discussion of multiple-language support in the NcDialog API.

gString Public Methods

What follows is a list of all public methods of the gString class.
Methods are arranged in functional groups.

gString Instantiation

The following are the ’constructors’ for the gString class.

For those new to C++, a constructor creates an ’instance’ of the class. An instance is a particular, named object, and can be thought of as a complex variable.

• gString ( void ) ;

    Input  :
       none
    Returns:
       nothing
  

  Constructor: Initialize members to default values (NULL string).

  
  
• gString ( const char* usrc, short charLimit=gsMAXCHARS ) ;

    Input  :
       usrc      : pointer to a UTF-8-encoded, null-terminated string
       charLimit : (optional, gsMAXCHARS by default)
                   maximum number of characters from source array to 
                   convert
    Returns:
       nothing
  

  Constructor: Convert specified UTF-8-encoded source to gString.

  
  
• gString ( const wchar_t* wsrc, short charLimit=gsMAXCHARS ) ;

    Input  :
       wsrc      : pointer to a wchar_t-encoded, null-terminated string
       charLimit : (optional, gsMAXCHARS by default)
                   maximum number of characters from source array to 
                   convert
    Returns: nothing
  

  Constructor: Convert specified wchar_t (’wide’) source to gString.

  
  
• gString ( short iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( unsigned short iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( int iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( unsigned int iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( long int iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( unsigned long int iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( long long int iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
• gString ( unsigned long long int iVal, short fWidth, bool lJust = false,
            bool sign = false, bool kibi = false, fiUnits units = fiK ) ;
  
  

    Input  :
       iVal  : value to be converted
               Supported value range: plus/minus 9.999999999999 terabytes
       fWidth: field width (number of display columns)
               range: 1 to FI_MAX_FIELDWIDTH
       lJust : (optional, false by default)
               if true, strip leading spaces to left-justify the value
               in the field. (resulting string may be less than fWidth)
       sign  : (optional, false by default)
               'false' : only negative values are signed
               'true'  : always prepend a '+' or '-' sign.
       kibi  : (optional, false by default)
               'false' : calculate as a decimal value (powers of 10)
                         kilobyte, megabyte, gigabyte, terabyte
               'true'  : calculate as a binary value (powers of 2)
                         kibibyte, mebibyte, gibibyte, tebibyte
       units  : (optional) member of enum fiUnits (fiK by default)
                specifies the format for the units suffix.
                Note that if the uncompressed value fits in the field,
                then this parameter is ignored.
  
    Returns: nothing
       Note: if field overflow, field will be filled with '#' characters.
  

  Constructor: Convert specified integer value to gString.
  Please see Integer Formatting, 'formatInt' method group for formatting details.

  
  
• gString ( const char* fmt, const void* arg1, ... )
            __attribute__ ((format (gnu_printf, 2, 0))) ;

    Input  :
       fmt       : a format specification string in the style of 
                   sprintf(), swprintf() and related formatting 
                   C/C++ functions.
       arg1      : pointer to first value to be converted by 'fmt'
       ...       : optional arguments (between ZERO and gsfMAXARGS - 1)
                   Each optional argument is a POINTER (address of) the 
                   value to be formatted.
    Returns:
       nothing
  

  Constructor: Convert formatting specification and its arguments to gString. Please refer to the compose() method (see Formatted Assignments) for more information.

  Technical Note: There is no constructor using a “const wchar_t* fmt” format specification because it would conflict with the constructor which limits the number of characters used to initialize the instance.

  
  
• gString ( const gsForm& gsf, short charLimit=gsMAXCHARS ) ;

    Input  :
       gsf       : initialized gsForm class object containing parameters 
                   for creating a formatted text string.
       charLimit : (optional, gsMAXCHARS by default)
                   maximum number of characters from source array to 
                   convert
    Returns:
       nothing
  

  DEPRECATED: May be removed in a future release.
  This method seemed like a good idea back in 2011, but neither we, nor our beta testers have ever had a desire to use it.

  Constructor: Convert formatting instructions in gsForm class object to gString. See compose() for more information.

  
  
• ~gString ( void ) ;

    Input  :
       none
    Returns:
       nothing
  

  Destructor: Release all resources associated with the gString object.

  Object is destroyed either when it goes out of scope, or by explicitly deleting the object.

  For those new to C++, please note that if you use the ’new’ keyword to create objects, then those objects persist (take up space) until you explicitly delete them or until the application is closed, even if the pointer to the object has gone out-of-scope. See examples below.

  
  

  Examples

  void calling_method ( void )
  {
     gString *gsPtr = playful_kitten ( "Hello World!" ) ;
  
     // report contents of object created by called method
     wcout << gsPtr->gstr() << endl ;
     delete gsPtr ; // delete object created by called method
  }
  
  gString* playful_kitten ( const char* msg )
  {
     gString gs_local( "I love tuna!" ) ;  // local object
     gString *gsPtr1 = new gString,        // global object
             *gsPtr2 = new gString(msg) ;  // global object (initialized)
     gString *gsArray = new gString[4] ;   // global array
  
     *gsPtr1 = gs_local ;   // be a kitten: play with the strings...
     gsArray[2] = *gsPtr2 ;
     gsArray[3] = "Scratch my belly!" ;
     gsArray[1] = gsArray[3] ;
  
     delete gsPtr1 ;      // delete object referenced by gsPtr1
     delete [] gsArray ;  // delete object array referenced by gsArray
     return gsPtr2 ;      // return pointer to object referenced by gsPtr2
                          // (caller is responsible for deleting object)
  }           // 'gs_local' goes out of scope and is destroyed here
  

Assignment Operators

For those new to C++, an assignment operator assigns (initializes) the object to the left of the ’=’ using the data on the right of the ’=’. You may also hear the term ’overloaded operator’. This just means that the ’=’ assignment operator may be defined in more than one way, so it will perform different tasks according to the context or circumstance.

• void operator = ( const char* usrc ) ;

    Input  :
       usrc  : pointer to an array of UTF-8-encoded characters
    Returns:
       nothing
  

  Assignment operator: converts UTF-8-encoded source to gString.

• void operator = ( const wchar_t* wsrc ) ;

    Input  :
       wsrc  : pointer to an array of wchar_t 'wide' characters
    Returns:
       nothing
  

  Assignment operator: converts wchar_t (’wide’) source to gString.

• void operator = ( const gString& gssrc ) ;

    Input  :
       gssrc : gString object to be copied (by reference)
    Returns:
       nothing
  

  Assignment operator. Copies one gString object to another.

• void operator = ( const gsForm& gsf ) ;

    Input  :
       gsf   : an initialized gsForm object (by reference)
    Returns:
       nothing
  

  DEPRECATED: May be removed in a future release.
  Assignment operator: Converts gsForm-class instructions to gString.

Examples

char utf8Data[] = { "Youth is wasted on the young." } ;
gString gs1, gs2 ;

gs1 = utf8Data ;
gs2 = gs1 ;
wcout << gs2 << endl ;
 - - -> Youth is wasted on the young.

Formatted Assignments

• const wchar_t* compose ( const wchar_t* fmt, ... )
                           __attribute__ ((format (gnu_wprintf, 2, 0))) ;
  
• const wchar_t* compose ( const char* fmt, ... )
                           __attribute__ ((format (gnu_printf, 2, 0))) ;

    Input  :
       fmt  : a format specification string in the style of sprintf(),
              swprintf() and related formatting C/C++ functions.
       ...  : optional arguments (between ZERO and gsfMAXARGS)
              Each optional argument is a POINTER (address of) the value
              to be formatted.
              - Important Note: There must be AT LEAST as many optional
                arguments as the number of format specifiers defined in
                the formatting string. Excess arguments will be ignored;
                HOWEVER, too few arguments will result in an application
                crash. You have been warned.
    Returns:
       const wchar_t* to formatted data
  

  Create formatted text data from a format specification string including between ZERO and gsfMAXARGS format specifications and their corresponding argument pointers.

  Supported data types:
   %d, %i  integer (decimal)
   %o      integer (octal)
   %u      integer (unsigned)
   %x, %X  integer (hex lower or upper case)
   %f      floating point (fixed point)
   %e, %E  floating point (scientific notation, lower/uppercase)
   %g, %G  floating point (normal/exponential, lower/uppercase)
   %a, %A  floating point (hex fraction)
   %c      character
   %C      character (alias for %lc)
   %s      string
   %S      string (alias for %ls)
   %p      pointer
   %b, %B  (extension to swprintf - see description below)
   %m      capture 'errno' description string (see /usr/include/errno.h)
   %n      number of characters printed so far
           (value written to corresponding argument's location)
   %%      literal '%'
  
  See man pages for the C/C++ function 'swprintf' or
  'Table of Output Conversions' for additional details.
  

Examples

char      Greeting[] = { "Hello!" } ;
int       iValue = 27064 ;
long long int qValue = 7842561 ;
long int  lValue = 485772 ;
short int sValue1 = 28875, sValue2 = -261, sValue3 = 529 ;
bool      flagValue = true ;
float     fltValue = 278.5610234 ;
double    dblValue = 9982.5610234 ;
gString gs ;
gs.compose( "%s - %d %12hd, %-hi, %#hx %08lXh %lld %hhd",
            Greeting, &iValue, &sValue1, &sValue2, &sValue3,
            &lValue, &qValue, &flagValue ) ;
wcout << gs << endl ;
 - - -> Hello! - 27064        28875, -261, 0x211 0007698Ch 7842561 1
gs.compose( "floating downstream:%10.2f and doubling our pace:%.4lf",
            &fltValue, &dblValue ) ;
wcout << gs << endl ;
 - - -> floating downstream:    278.56 and doubling our pace:9982.5610

See also formatted instantiation: see gString Instantiation.

Important Note on Formatting

Because THE PARAMETERS ARE POINTERS TO THEIR DATA, similar to the C/C++ library function ’sscanf’ and friends, the compiler cannot perform automatic promotions from short int* to int* or from float* to double*, and so-on as it would for swprintf.

This implementation was selected because a) it eliminates data-width conflicts when moving among hardware platforms, and b) it reduces code size while increasing performance.

This implementation relies on you, the designer, to use care that the data type you specify in the formatting string matches the data type of the variable referenced by its parameter pointer AND that you use the ’address-of’ (’&’) operator to reference non-pointer variables. Note also that ’literal’ values may not be used as parameters because literals have no address.

The following constructs will produce errors:

gString gs ;
char   grade = 'A' ;
short  age   = 21 ;
int    sat   = 1550 ;
double gpa   = 3.75 ;

   // These examples fail to use the 'address-of' operator for the 
   // referenced variables, and will cause a 'segmentation fault' 
   // i.e. an application crash.
   gs.compose( "My grade is an %c", grade ) ;
   gs.compose( "I got a %d on my SAT.", sat ) ;
   // The above should be:
   gs.compose( "My grade is an %c", &grade ) ;
   gs.compose( "I got a %d on my SAT.", &sat ) ;

   // These examples use mismatched format-specification/variable 
   // reference. This will result in either bad data out OR will 
   // cause a memory-access violation.
   gs.compose( "I can't wait to be %d.", &age ) ;
   gs.compose( "My GPA is %1.3f", &gpa ) ;
   gs.compose( "The hex value of %c is: %#x", &grade, &grade ) ;
   gs.compose( "My GPA is %1.3lf", 3.88 ) ; // (literal value)
   // The above should be:
   gs.compose( "I can't wait to be %hd.", &age ) ;
   gs.compose( "My GPA is %1.3lf", &gpa ) ;
   gs.compose( "The hex value of %c is: %#hhx", &grade, &grade ) ;

Parameter Type Checking:
Unfortunately, type-checking of wchar_t formatting strings is not yet supported by the gnu (v:4.8.0) compiler, (but see wchar.h which is preparing for the future). Thus, use care when constructing your ’wchar_t fmt’ formatting string. The ’char fmt’ string IS type-checked.

IMPORTANT NOTE:
Depending on your compiler version, you may get a warning when using the '%b' binary format specification (described below):
"warning: unknown conversion type character ‘b’ in format [-Wformat=]"
This is because the preprocessor does not recognize our custom format specifier. If this happens, use a ’wchar_t’ (wide) formatting template to avoid the preprocessor type checking.

Instead of:
      gs.compose( "bitmask: %b", &wk.mevent.eventType );
Use this (not type checked by the preprocessor):
      gs.compose( L"bitmask: %b", &wk.mevent.eventType );

Formatted binary output (extension to swprintf)

We implement an extension to the swprintf output-conversion-specifiers for binary formatted output. We have found this formatting option useful when working with bit masks, for verifying bit-shifting operations during encryption/decryption and other uses.

• Base formatting specifier:
  
  %b , %B Note that the lower-case / upper-case variants have identical function, and indicate only the case of the identifier character. See format modifiers for data size.
• Format modifiers for data size are the same as for swprintf:
  
  hh , h , l , ll , L , q Examples: %hhb %hB %llB %qb
• Format modifier for prepending of a data-type indicator.
  
  '#' (hash character) This is the same principle as for prepending a '0x' indicator to hex output, and will place either a 'b' or 'B' character at the beginning of the output. Examples: %#hhb -> b0101.1010 %#hhB -> B0101.1010
• Format modifier for appending of a data-type indicator.
  
  '-#' (minus sign and hash character) Rather than prepending the indicator, the indicator will be append to the end of the output. Examples: %-#hhb -> 0101.1010b %-#hhB -> 0101.1010B
• Format modifier for specifying the group-seperator character.
  
  By default, the bit groups are seperated by a '.' (fullstop) character. To specify an alternate seperator character: % hB -> 0111 0101 1010 0001 (' ' (space) as seperator) %_hB -> 0111_0101_1010_0001 ('_' (underscore) as seperator) %#/hB -> B0111/0101/1010/0001 ('/' (slash) as seperator) %-#-hB -> 0111-0101-1010-0001B ('-' (dash) as seperator) Valid seperator characters are any printable ASCII character that IS NOT alphabetical, IS NOT a number, and IS NOT a '.'(fullstop)
• Format modifier for specifying bit grouping.
  
  By default, bits are formatted in groups of four (4 nybble); however, if desired, bits can be formatted in groups of eight (8 byte): %.8hB -> 01110101.10100001 %-.8hB -> 01110101-10100001 %# .8hB -> B01110101 10100001 %-#`.8hb -> 01110101`10100001b

Field-width specification (swprintf bug fix)

The standard library ’swprintf’ function has a design flaw for format specifications that include a field-width specifier.

’swprintf’ pads the string to the specified number of CHARACTERS, not the number of COLUMNS as it should do. For ASCII numeric source values this is not a problem because one character equals one display column. For string source data, however, if the source string contains characters that require more than one display column each, then the output may be too wide.

Therefore, for string-source-formatting specifications ONLY:
          (examples: "%12s"  "%-6s"  "%16ls"  "%5S"  "%-24S")
we compensate for this ethnocentric behavior by interpreting the field-width specifier as number-of-columns, NOT number-of-characters. For non-ASCII string data, this will result in output that appears different (and better) than output created directly by the ’swprintf’ function.

Unsupported format specifications

Conversion modifiers that are not fully supported at this time:
                       ’j’, ’z’, ’t’, ’%[’
Also, the ’*’ field-width specification or precision specification which uses the following argument as the width/precision value IS NOT supported.

Integer Formatting

• bool formatInt ( short iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( unsigned short iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( int iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( unsigned int iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( long iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( unsigned long iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( long long iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  
• bool formatInt ( unsigned long long iVal, short fWidth,
                   bool lJust = false, bool sign = false,
                   bool kibi = false, fiUnits units = fiK ) ;
  

  Input  :
     iVal  : value to be converted
             Supported value range: plus/minus 9.999999999999 terabytes
     fWidth: field width (number of display columns)
             range: 1 to FI_MAX_FIELDWIDTH
     lJust : (optional, false by default)
             if true, strip leading spaces to left-justify the value
             in the field. (resulting string may be less than fWidth)
     sign  : (optional, false by default)
             'false' : only negative values are signed
             'true'  : always prepend a '+' or '-' sign.
     kibi  : (optional, false by default)
             'false' : calculate as a decimal value (powers of 10)
                       kilobyte, megabyte, gigabyte, terabyte
             'true'  : calculate as a binary value (powers of 2)
                       kibibyte, mebibyte, gibibyte, tebibyte
     units  : (optional) member of enum fiUnits (fiK by default)
              specifies the format for the units suffix.
              Note that if the uncompressed value fits in the field,
              then this parameter is ignored.

  Returns:
     'true' if successful
     'false' if field overflow (field will be filled with '#' chars)
             See notes below on field overflow.

Convert an integer value into a formatted display string of the specified width. Value is right-justified in the field, with leading spaces added if necessary (but see ’lJust’ parameter).

Maximum field width is FI_MAX_FIELDWIDTH. This is wide enough to display a 18-digit, signed and comma-formatted value: '+9,876,543,210,777'

Examples

1) Simple comma formatted output if specified field-width is sufficient.
   345    654,345    782,654,345    4,294,967,295

2) Output with values compressed to fit a specified field width.
   12.3K    999K    12.345M    1.234G    4.3G

   
gString gs ;      // gString object

3) Convert a signed integer value:
   int iValue = 28954 ;

   // field width == 8, right justified (note: compression unnecessary)
   gs.formatInt( iValue, 8 ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :  28,954:

   // field width == 8, left justified (note: compression unnecessary)
   gs.formatInt( iValue, 8, true ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :28,954:

   // field width == 6
   gs.formatInt( iValue, 6 ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :28.95K:

   // field width == 6 with forced sign
   gs.formatInt( iValue, 6, false, true ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :+29.0K:

   // field width == 5
   gs.formatInt( iValue, 5 ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :29.0K:

   iValue = -28954 ;    // convert negative source value

   // field width == 8, right justified (note: compression unnecessary)
   gs.formatInt( iValue, 8 ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  : -28,954:

   // field width == 8, left justified (note: compression unnecessary)
   gs.formatInt( iValue, 8, true ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :-28,954:

   // field width == 6
   gs.formatInt( iValue, 6 ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :-29.0K:

   // field width == 5
   gs.formatInt( iValue, 5 ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  : -29K:

4) Convert an unsigned long long integer value (field width == 11):
   unsigned long long int qValue = 39000009995 ;

   // decimal compression (gigabytes) with "official" IEC suffix
   gs.formatInt( qValue, 11, false, false, false, fikB ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :39.000010gB:

   // binary compression (gibibytes) with "official" IEC suffix
   gs.formatInt( qValue, 11, false, false, true, fiKiB ) ;
   wcout << ':' << gs << ':' << endl ;
    - - >  :38.08595GiB:

Please see (NcDialog test application, ’Dialogw’ for more examples.)

Notes on the formatInt group

The kilo/kibi controversy

The IEC (International System of Quantities) recommends lower-case for metric (powers of 10) and upper-case for binary (powers of 2). However, unless you must be accurate in presenting the data according to IEC standard, it is recommended that you choose the format according to: your space requirements, visual appeal, and clear communication with your users.
If you blindly follow style standards against your own better judgement, then be forever labelled as a weenie.

formatInt field overflow

As described above, the actual formatting of a fixed-width integer field depends on a number of factors. Every effort is made to compress the data to fit within the field while retaining an accurate representation of the numeric value.

There are cases, however, where it is not possible to represent the data within the specified field width. When this occurs, the entire field will be filled with HASH characters '#'.

The specified field must be wide enough to accomodate either the entire, uncompressed value, or the combination of compressed value, units designator and sign (if any). The following situations may cause field overflow.

Fields of seven(7) or more columns can display any formatted value without danger of overflow.

Data Access

• const wchar_t* gstr ( void ) const ;

    Input  :
       none
    Returns:
       const pointer to array of wchar_t characters
  

  Return a const pointer to the wchar_t (wide) character array.

  
  
• const wchar_t* gstr ( short& charCount ) const ;

    Input  :
       charCount : (by reference, initial value ignored)
                   receives number of characters in array, 
                   including null terminator
    Returns:
       const pointer to array of wchar_t characters
  

  Return a const pointer to the wchar_t (wide) character array, along with the number of characters in the array (including the null terminator).

  
  
• const char* ustr ( void ) const ;

    Input  :
       none
    Returns:
       const pointer to array of UTF-8 characters
  

  Return a const pointer to the char (UTF-8) character array.

  
  
• const char* ustr ( short& charCount, short& byteCount ) const ;

    Input  :
       charCount : (by reference, initial value ignored)
                   receives number of characters in array, 
                   including null terminator
       byteCount : (by reference, initial value ignored)
                   receives number of bytes in array, 
                   including null terminator
    Returns:
       const pointer to array of UTF-8 characters
  

  Return a const pointer to the char (UTF-8) character array, along with the number of characters and the number of bytes in the array (including the null terminator).

Examples

short charCount, byteCount ;
gString gs( "Wherever you go, there you are!" ) ;

const wchar_t* wPtr = gs.gstr() ;
const wchar_t* wPtr = gs.gstr( charCount ) ;
const char* utf8Ptr = gs.ustr() ;
const char* utf8Ptr = gs.ustr( charCount, byteCount ) ;

Copying Data

• short copy ( char* uTarget, short maxBytes,
     short maxCols=(gsMAXCHARS*2) ) const ;

    Input  :
       uTarget  : pointer to target array to receive UTF-8-encoded text
       maxBytes : maximum number of bytes to copy (incl. NULL terminator)
       maxCols  : (optional, default == gsMAXCHARS*2)
                  maximum number of display-columns to copy
    Returns:
       number of bytes copied (incl. NULL terminator)
  

  Copy gString text to specified target buffer.

  
  
• short copy ( wchar_t* wTarget, short maxChars,
     short maxCols=(gsMAXCHARS*2) ) const ;

    Input  :
       wTarget  : pointer to target array to receive wchar_t 'wide' text
       maxChars : maximum number of characters to copy (incl. NULL)
       maxCols  : (optional, default == gsMAXCHARS*2)
                  maximum number of display-columns to copy
    Returns:
       number of characters copied (incl. NULL terminator)
  

  Copy gString text to specified target buffer.

  
  
• std::wostream& operator<< ( std:wostream& os, const gString& gs2 );

    Input  :
       IMPLIED reference to the output stream
       IMPLIED reference to the gString object
    Returns: reference to the specified output stream
  

  !! NON-MEMBER METHOD !!
  Insertion operator: Copies the contents of the gString object into the ’wcout’ (wide) standard output stream.

  Note that due to the way the output stream is defined, you cannot mix ’cout’ (narrow) and ’wcout’ (wide) output streams indiscriminately. -- If ’wcout’ is called first, then ’cout’ is disabled. -- If ’cout’ is called first, then both narrow and wide channels are active. -- ’wcout’ handles both narrow and wide data, however, ’cout’ handles ONLY narrow data. This is not related to gString, but is a characteristic of the default C++ output stream itself. We recommend that you always use the ’wcout’ stream in console applications for both narrow and wide text data.
  
  
• std::ostream& operator<< ( std:ostream& os, const gString& gs2 );

    Input  :
       IMPLIED reference to the output stream
       IMPLIED reference to the gString object
    Returns: reference to the specified output stream
  

  !! NON-MEMBER METHOD !!
  Insertion operator: Copies the contents of the gString object into the ’cout’ (narrow) standard output stream.

  IMPORTANT NOTE: Access to the narrow output stream is provided for convenience only. It is recommended that the wide stream version (above), if available on your system, be used exclusively.
  
  
• short substr ( char* uTarget, short offset, short charCnt ) const ;
• short substr ( wchar_t* wTarget, short offset, short charCnt ) const ;
• short substr ( gString& wTarget, short offset, short charCnt ) const ;

    Input  :
       targ    : (by reference, initial contents ignored)
                 receives null-terminated contents of specified
                 character range
                 -- If target buffer is a char*, then data returned is 
                    a UTF-8 text string.
                 -- If target buffer is a wchar_t*, then data returned is 
                    a wchar_t (wide) text string.
                 IMPORTANT NOTE: It is the caller's responsibility to 
                 specify a target buffer large enough to hold the data.
                 Recommended: wchar_t wbuff[gsMAXCHARS]; or 
                              char ubuff[gsMAXBYTES];
                 -- If target buffer is a gString object, then both 
                    UTF-8 and wchar_t data are returned 
                    (with no chance of target buffer overflow).
  
       offset  : character index at which substring begins
                 (this IS NOT a byte index)
       charCnt : number of characters to copy (not incl. NULL terminator)
    Returns:
       if target is a wchar_t* or gString object, then returns number of
         characters written to target (not including the NULL terminator)
       if target is a char*, then returns number of bytes written to
         target (not including the NULL terminator)
  
       Note: returns ZERO if either 'offset' or 'charCnt' out of range
       Note: If 'charCnt' extends beyond the end of the source data, 
             then returns the available data.
  

  Copy the specified character range to target buffer.
  These methods copy the indicated substring (null terminated) to the target buffer, leaving the original data unchanged.

  If you have a fixed-format field, then the offset and character count will be known in advance. Otherwise you can use the ’find()’ method to locate the substring to be copied.

  Please Note: The number of bytes can NEVER be assumed to be the same as the number of characters.
  Please refer to the ’Multi-language Support’ chapter of the ’ncdialogapi’ documentation.

Examples

gString gs( "That's not flying, that's falling -- with style!\n"
            "Buzz Lightyear" ) ;
char utf8Data[gsMAXBYTES] ;
wchar_t wideData[gsMAXCHARS] ;

gs.copy( utf8Data, gs.utfbytes() ) ;
gs.copy( wideData, gs.gschars() ) ;

gString gstream( "You're a child's TOY! -- Woody" ) ;
wcout << gstream << endl ;

// get a copy of the first word starting with 'c'
gString AusAnimal( "Aardvark Kangaroo Cockatoo Dingo Wombat " ) ;
gString gsc ;
short b = AusAnimal.find( " c" ) ;
if ( b >= 0 )
{
   short e = AusAnimal.find( L' ', b + 1 ) ;
   if ( e > b )
   {
      AusAnimal.substr( gsc, (b + 1), (e - b - 1) ) ;
      wcout << gsc << endl ;
   }
}
 - - -> Cockatoo

Modifying Existing Data

• short append ( const wchar_t* wPtr ) ;
  
• short append ( const char* uPtr ) ;
  
• short append ( const wchar_t wChar ) ;

    Input  :
       wPtr  : pointer to array of wchar_t 'wide' text to be appended
               OR
       uPtr  : pointer to array of char UTF-8 text to be appended
               OR
       wChar : a single, 'wide' character
    Returns:
       number of characters in resulting string (incl. NULL terminator)
       Note: if value returned equals gsMAXCHARS, then 
             some data MAY HAVE BEEN discarded.
  

  Append text to existing gString text data up to a combined length of gsMAXCHARS. Characters in excess of the maximum will not be appended.

  Example

  gString gs( L"Be kind to your manager." ) ;
  gs.limitChars( gs.gschars() - 2 ) ;
  gs.append( L", and other lower forms of life." ) ;
  wcout << gs << endl ;
   - - -> Be kind to your manager, and other lower forms of life.
  

  
  
  
• short append ( const wchar_t* fmt, const void* arg1, ... )
                 __attribute__ ((format (gnu_wprintf, 2, 0)));
  
• short append ( const char* fmt, const void* arg1, ... )
                 __attribute__ ((format (gnu_printf, 2, 0)));

    Input  :
       fmt  : a format specification string in the style of sprintf(),
              swprintf() and related formatting C/C++ functions.
       arg1 : pointer to first value to be converted by 'fmt'
       ...  : optional arguments (between ZERO and gsfMAXARGS - 1)
              Each optional argument is a POINTER (address of) the value
              to be formatted.
  
    Returns:
       number of characters in resulting string (incl. NULL terminator)
       Note: if return equals gsMAXCHARS, then
             some data MAY HAVE BEEN discarded.
  

  Append formatted text data to existing gString text data up to a combined length of gsMAXCHARS. Characters in excess of the maxmum will not be appended.

  Please refer to the ’compose’ method (see Formatted Assignments) for more information on converting data using a format specification string.

  Example

  short gaddress = 2840 ;
  wchar_t gdirection = L'E' ;
  const wchar_t* gstreet = L"Colorado Blvd." ;
  double gcost = 29.95 ;
  gString gs( "Gorilla Men's Clothing" ) ; // existing text
  
  gs.append( ", %hd %C %S\n  Dress shirts on sale, $%.2lf.", 
             &gaddress, &gdirection, gstreet, &gcost ) ;
  
  wcout << gs << endl ;
   - - -> Gorilla Men's Clothing, 2840 E Colorado Blvd.
            Dress shirts on sale, $29.95.
  

  
  
  
• short insert ( const wchar_t* wPtr, short offset = 0 ) ;
  
• short insert ( const char* uPtr, short offset = 0 ) ;
  
• short insert ( wchar_t wChar, short offset = 0 ) ;

    Input  : 
       wPtr  : pointer to array of wchar_t 'wide' text to be inserted
               OR
       uPtr  : pointer to array of char UTF-8 text to be inserted
               OR
       wChar : a single wchar_t 'wide' character
       offset: (optional, ZERO by default)
               character offset at which to insert specified text into
               existing text.
               Note: if specified 'offset' > number of characters in
                     existing text, then acts like 'append' method.
    Returns:
       number of characters in resulting string (incl. NULL terminator)
       Note: if value returned equals gsMAXCHARS, then 
             some data MAY HAVE BEEN discarded.
  

  Insert text into existing gString text data up to a combined length of gsMAXCHARS. Characters in excess of the maximum will be truncated.

  Example

  gString gs( L"Remember to hurt people!" ) ;
  gs.insert( L"NOT ", 9 ) ;
  wcout << gs << endl ;
   - - -> Remember NOT to hurt people!
  

  
  
  
• short limitChars ( short charCount ) ;

    Input  :
       charCount : maximum number of characters allowed in formatted data 
                   (not including NULL) Range: 1 to gsMAXCHARS-1
    Returns:
       number of characters in the adjusted data (including NULL)
  

  Truncate the data to no more than charCount display characters.
  Insert a null terminator after the specified number of characters.

  Example

  gString gs( "This shirt is available in yellow or red." ) ;
  gs.limitChars( 34 ) ;
  gs.append( "only." ) ;
  wcout << gs << endl ;
   - - -> This shirt is available in yellow only.
  

  
  
  
• short limitCols ( short colCount ) ;

    Input  :
       colCount : maximum number of display columns allowed in formatted data
                  Range: 1 to (gsMAXCHARS * 2)
    Returns:
       number of columns needed to display the adjusted data
       Note: If specified column count occurs in mid-character, then the 
             partial character will be removed from the string.
  

  Truncate the data to no more than colCount display columns. Insert a null terminator after the number of characters required to fill the specified number of display columns.

  Example

  gString gs( "The manual is located at:\n"
              "http://cdn.funcom.com/aoc/pdf/aoc_manual.pdf" ) ;
  gs.limitCols( 55 ) ;
  wcout << gs << endl ;
   - - -> The manual is located at:
          http://cdn.funcom.com/aoc/pdf/
  
  Note that there are 25 display columns for the first line, (the newline 
  character requires no column), and 30 columns remain on the second line.
  

  
  
  
• short shiftChars ( short shiftCount, wchar_t padChar = L’ ’ ) ;

    Input  :
       shiftCount: < ZERO: shift data to the left, discarding the
                           specified number of characters from the
                           beginning of the array
                   > ZERO: shift data to the right, padding the vacated
                           positions on the left with 'padChar'
                   ==ZERO: do nothing
       padChar   : (optional, SPACE character, 0x20 by default)
                   when shifting data to the right, use this character
                   to fill the vacated character positions
                   NOTE: Specify a one-column character ONLY as the
                   padding character. (multi-column characters ignored)
    Returns:
       number of characters in adjusted array
  

  Shift text data by the specified number of characters.

  Note for writers of RTL (right-to-left) languages:
   In the above descriptions, the terms 'left' and 'right' are used for 
   convenience, but actually 'left' refers to the head of the data 
   and 'right' refers to the tail.
  

  Example

  gString gs( "Your balance is: 2,521,697.56 USD" ) ;
  gs.shiftChars( -17 ) ;
  wcout << gs << endl ;
   - - -> 2,521,697.56 USD
  gs.shiftChars( 5, L'#' ) ;
  wcout << gs << endl ;
   - - -> #####2,521,697.56 USD
  
  Note: For this example, the optional fill character used for 
  right-shift is L'#'. The default fill character is space (L' ').
  

  
  
  
• short shiftCols ( short shiftCount, wchar_t padChar = L’ ’ ) ;

    Input  :
       shiftCount: < ZERO: shift data to the left, discarding the
                           number of characters equivalent to the
                           specified number of display columns
                           NOTE: May discard one extra column if count
                           falls within a multi-column character.
                   > ZERO: shift data to the right, padding the vacated
                           positions on the left with 'padChar'
                   ==ZERO: do nothing
       padChar   : (optional, SPACE character, U+0020 by default)
                   when shifting data to the right, use this character
                   to fill the vacated column positions
                   NOTE: Specify a one-column character ONLY as the
                   padding character. (multi-column characters ignored)
    Returns:
       number of display columns in adjusted array
  

  Shift text data by the specified number of display columns.

  Note for writers of RTL (right-to-left) languages:
   In the above descriptions, the terms 'left' and 'right' are used for 
   convenience, but actually 'left' refers to the head of the data 
   and 'right' refers to the tail.
  

  Example

  gString gs( "您的帐户余额是500元" ) ; // "Your account balance is 500 yuan"
  gs.shiftCols( -14 ) ;
  wcout << gs << endl ;
   - - -> 500元
  gs.shiftCols( 5, L'.' ) ;
  wcout << gs << endl ;
   - - -> .....500元
  
  Note: Most Chinese characters are two display columns wide, 
  therefore we shift 14 columns (7 characters) out on the left.
  For this example, the optional fill character used for 
  right-shift is L'.' (U+002E, ASCII full stop). 
  The Chinese full-stop (U+3002) MAY NOT be used as a fill 
  character because it is a two-column character.
  

  
  
  
• short padCols ( short fieldWidth, wchar_t padChar = L’ ’,
                  bool centered = false );

    Input  :
       fieldWidth: number of columns for the adjusted data array
       padChar   : (optional, ASCII space 0x20 by default)
                   character with which to pad the data
                   Note: Specify a one-column character ONLY.
                         Multi-column characters will be ignored.
       centered  : (optional, 'false' by default)
                   if 'false', all padding will be appended at the end 
                               of the existing data
                   if 'true',  padding will be equally divided between 
                               the beginning and end of the existing data
  
    Returns:
       number of display columns in the adjusted array
  
  

  Append padding to the existing string data to achieve the specified number of display columns.

  If the 'centered' flag is set, the padding will be divided equally between the beginning and end of the data to achieve the specified field width. Note that if an odd number of columns is to be added, then the odd column will be placed at the end of the data.

  The ‘padCols’ method calculates the number of padding characters needed to fill out the specified field width.

  The default padding character is the ASCII space character (20 hex).
  Any single-column character may be specified as an alternate padding character.

  Padding will be added until either the specified number of columns is reached, OR until the array contains the maximum number of characters (gsMAXCHARS).

  If the fieldWidth specified is <= the current width of the data, then the data will not be modified.

  Example

  gString gs( "This is a test." );
  
  gs.padCols( 30 );              ==> "This is a test.               "
  gs.padCols( 30, L'#' );        ==> "This is a test.###############"
  gs.padCols( 30, L'#', true );  ==> "#######This is a test.########"
  
  // To create a right-justified field, use 'shiftCols' (see above):
  gs.shiftCols( (30 - gs.gscols()) );
                                 ==> "               This is a test."
  gs.shiftCols( (30 - gs.gscols()), L'#' );
                                 ==> "###############This is a test."
  

  
  
  
• short strip ( bool leading = true, bool trailing = true );

    Input  :
       leading  : (optional, 'true' by default)
                  if 'true', strip leading whitespace
                  if 'false', leading whitespace unchanged
       trailing : (optional, 'true' by default)
                  if 'true', strip trailing whitespace
                  if 'false', trailing whitespace unchanged
  
    Returns:
       number of characters in modified string (incl. NULL terminator)
  

  Strip (remove) leading and/or trailing whitespace from the string data.

  Whitespace characters are defined as:
  0x0020 single-column ASCII space
  0x3000 two-column CJK space
  0x0A linefeed character
  0x0D carriage-return character
  0x09 horizontal-tab character
  0x0B vertical-tab character
  0x0C formfeed character
  

  “Leading” whitespace is space characters from the beginning of the data to the first non-space character. “Trailing” whitespace is from after the last non-space character through the end of the data.

  By default, both leading and trailing whitespace will be removed; however, this action may be modified by resetting the appropriate parameter to ‘false’.

  
  
  
• short erase ( const gString& src,
                short offset = 0, bool casesen = false );
  
• short erase ( const wchar_t* src,
                short offset = 0, bool casesen = false );
  
• short erase ( const char* src,
                short offset = 0, bool casesen = false );
  
• short erase ( const wchar_t src,
                short offset = 0, bool casesen = false );

    Input  :
       src    : source data to be matched, one of the following:
                -- pointer to a UTF-8 string (max length==gsMAXBYTES)
                -- pointer to a wchar_t string (max length==gsMAXCHARS)
                -- a gString object containing the source (by reference)
                -- a single, wchar_t character
       offset : (optional, ZERO by default)
                character index at which to begin search
                NOTE: This is a character index, NOT a byte offset.
       casesen: (optional, 'false' by default)
                if 'false', then scan IS NOT case sensitive
                if 'true, then scan IS case sensitive
                The way upper/lowercase are related is locale dependent;
  
    Returns:
       index of first character following the deleted sequence
       Note: This is the wchar_t character index, NOT a byte index
       Returns (-1) if:
         a) no matching substring found
         b) 'offset' out-of-range
         c) 'src' is an empty string or a NULL character
  
  

  Scan the data for a matching substring, and if found, erase (delete) the first occurance of the substring.

  Actual comparison is always performed against the ’wide’ character array using wcsncasecmp (or wcsncmp). Null terminator character IS NOT included in the comparison. These comparisons ARE locale dependent.

  
  
  
• short erase ( short offset = 0, short length = gsMAXCHARS ) ;

    Input  :
       offset : (optional, ZERO by default)
                index of first character of sequence to be erased
                NOTE: This is a character index, NOT a byte offset.
       length : (optional, gsMAXCHARS by default)
                if not specified, then erase all characters from
                   'offset' to end of data
                if specified, then erase the specified number of
                   characters beginning at 'offset'
  
    Returns:
       index of first character following the deleted sequence
       Note: This is the wchar_t character index, NOT a byte index
       Returns (-1) if:
         a) offset < ZERO
         b) offset >= number of characters in data
         c) length <= ZERO
       (data will not be modified)
  
  

  Erase (delete) the data sequence specified by ’offset’ and ’length’.

  ’offset’ is the index of the first character to be deleted, and ’length’ specifies the number of characters to delete.

  Example

  • If the ’length’ parameter specifies deletion of more characters than remain, then ’erase’ has the same effect as calling the ’limitChars’ method (i.e. truncates the string at ’offset’).
  • If the defaults for both ’offset’ and length’ are used, then the ’erase’ method has the same effect as calling the ’clear’ method (gString data are reset to an empty string).
  • Note that the NULL terminator will never be deleted.
  • Programmer’s Note:
    Stubs with 'int' arguments are also defined, but are included only to silence a compiler warning that the prototype erase(short, short); is ’ambiguous’. Actually, it is not ambiguous at all, but we believe that the use of pragmas is bad design, so it’s easier to include the stubs than to argue with the compiler. Internally, gString uses ’short int’ exclusively.

  Examples for 'erase'

  For the gString object containing the following verbal 
  exchange, erase all occurances of the word 'crapweasel'.
  
  gString gs( "Ross : Are you familiar with the word crapweasel?\n"
              "Paolo: No, I don't know crapweasel.\n"
              "Ross : You're a huge crapweasel!" );
  short index = ZERO ;
  while ( (index = gs.erase( " crapweasel", index )) >= ZERO ) ;
  
  Yields:
    "Ross : Are you familiar with the word?\n"
    "Paolo: No, I don't know.\n"
    "Ross : You're a huge!"
  
  Find the substring, "the the" and erase the extra "the".
  gString gs1( L"There are seven candidates in the the Primary Election." );
  gString gs2( L"the " );
  short index = gs1.find( "the the" );
  gs1.erase( index, (gs2.gschars() - 1) );
  
  Yields:
    "There are seven candidates in the Primary Election."
  

  
  
  
• short replace ( const wchar_t* src, const wchar_t* newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const wchar_t* src, const char* newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const wchar_t* src, const wchar_t newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const char* src, const wchar_t* newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const char* src, const char* newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const char* src, const wchar_t newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const wchar_t src, const wchar_t* newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const wchar_t src, const char* newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );
  
• short replace ( const wchar_t src, const wchar_t newtxt,
                  short offset = 0,
                  bool casesen = false, bool all = false );

    Input  :
       src    : source data to be matched
                -- pointer to a UTF-8 string
                -- pointer to a wchar_t string
                -- a single, wchar_t character
       newtxt : data to overwrite existing text
                -- pointer to a UTF-8 string
                -- pointer to a wchar_t string
                -- a single, wchar_t character
       offset : (optional, ZERO by default)
                character index at which to begin search
                NOTE: This is a character index, NOT a byte offset.
       casesen: (optional, 'false' by default)
                if 'false', then scan IS NOT case sensitive
                if 'true, then scan IS case sensitive
                The way upper/lowercase are related is locale dependent;
       all    : (optional, 'false' by default)
                if 'false', then replace only the first occurance found
                if 'true',  then replace all occurances of the specified
                            substring
  
    Returns:
       'true' if successful
       returns 'false' if error (existing data not modified):
         a) no matching source substring found
         b) 'src' is a empty string or a null character
         c) offset < ZERO or offset is beyond existing data
         d) modifying the data would cause buffer overflow (>gsMAXCHARS)
  

  Replace the specified source substring, or optionally all matching substrings with the provided substring.

  Actual comparison is always performed against the ’wide’ character array using wcsncasecmp (or wcsncmp). Null terminator character IS NOT included in the comparison. These comparisons ARE locale dependent.

  Examples for 'replace'

  Correct the spelling errors in the following data:
  gString gs( "The land near hare is full of Heres, hoping her and ther." ) ;
  
  bool okiday = gs.replace( L"hare", L"here" ) ;
  Yields:
    "The land near here is full of Heres, hoping her and ther."
  
  okiday = gs.replace( "Here", "Hare", ZERO, true ) ;
  Yields:
    "The land near here is full of Hares, hoping her and ther."
  
  okiday = gs.replace( L'p', L"pp" ) ;
  Yields:
    "The land near here is full of Hares, hopping her and ther."
  
  short index = gs.find( "her " ) ;
  okiday = gs.replace( "her", L"here", index, true, true ) ;
  Yields:
    "The land near here is full of Hares, hopping here and there."
  
  Then, replace all spaces ' ' with underscores '_'.
  okiday = gs.replace( L' ', L'_', ZERO, false, true ) ;
  Yields:
    "The_land_near_here_is_full_of_Hares,_hopping_here_and_there."
  

  
  
  
• short loadChars ( const wchar_t* wsrc, short charLimit,
                    bool append = false );
  
• short loadChars ( const char* usrc, short charLimit,
                    bool append = false );

  Load the specified number of characters from the source data. This is useful for extracting data from fixed-width fields when the contents of the field is unknown.
  gs.loadChars( StreetAddress1, 48 );

  By default, the new text REPLACES the existing text; however, the ’append’ parameter allows the new text to be appended to the existing text.

  The functionality is equivalent to the gString constructor which loads only the specified number of characters.
  See gString Instantiation.

  
  

    Input  :
       usrc     : pointer to a UTF-8 encoded string
       wsrc     : pointer to a wchar_t encoded string
       charLimit: maximum number of characters (not bytes) from source
                  array to load. Range: 1 through gsMAXCHARS.
                  The count should not include the NULL terminator
       append   : (optional, 'false' by default)
                  if 'false', replace existing text with specified text
                  if 'true', append new text to existing text
  
    Returns:
       number of characters in modified string (incl. NULL terminator)
  

  Examples for 'loadChars'

  Replace the existing text with the specified number of characters 
  from the source text.
  
  const char* Piggy =  // (56 characters)
             "Spider-pig, Spider-pig does whatever a Spider-pig does." ;
  gString gs( "Existing text." ) ;
  gs.loadChars( Piggy, 36 ) ;
  Yields:
    "Spider-pig, Spider-pig does whatever"
  
  Append specified number of characters from the source text to the 
  existing text.
  
  gs.loadChars( " it's told, because it's stupid.", 11, true ) ;
  Yields:
    "Spider-pig, Spider-pig does whatever it's told,"
  

  
  
  
• short textReverse ( bool punct = false,
                      bool para = false, bool rjust = false );
  

  Reverse the order of characters in the text string.

  If RTL text data displayed by your application is not formatted as desired, then this method may be used to reverse the character order before writing to the display. This is useful for manipulating both RTL (Right-To-Left) language text and mixed RTL/LTR text.

  The ’para’ parameter is useful for outputting columns of numeric data or when the column labels are in an RTL language (see example below).

  Although modern web browsers (Firefox, Opera, Chromium, etc.) usually handle RTL text correctly, other applications often do not. This is especially true of terminal emulator software.

  See also a discussion of multiple-language support in the NcDialog API.
  

    Input  :
       punct : (optional, 'false' by default)
               if 'false', invert entire string
               if 'true' AND if a punctuation mark is seen at either end
                  of the string, invert everything except the punctuation
                  mark(s). typically one of the following:
                  '.' ',' '?' '!' ';' ':' but see note below.
       para  : (optional, 'false' by default)
               if 'false', invert data as a single character stream
               if 'true',  invert data separately for each logical line
                           (line data are separated by newlines ('\n')
       rjust : (optional, 'false' by default)
               if 'false', do not insert right-justification padding
               if 'true',  insert padding for each logical line to
                           right-justify the data
                           (used to right-justify LTR output)
                           Note that right-justification is performed
                           ONLY if the 'para' parameter is true.
                           Otherwise, 'rjust' will be ignored.
  
    Returns:
       number of wchar_t characters in gString object
       (if return value >= gsMAXCHARS, data may have been truncated)
  

  Examples for 'textReverse'

  Note that the const Hebrew strings are written canonically in the source, but are displayed incorrectly in the terminal window by the info reader and by the HTML browser (sorry about that).

  // Hebrew: "Are you ready for lunch?"
  // Sometimes the terminal will inappropriately move the punctuation 
  // to the opposite end of the string.
  // To prevent this, use the 'punct' option.
  const wchar_t* const Lunch = L"?םיירהצ תחוראל ןכומ התא םאה" ;
  
  gString gs( Lunch ) ;
  gs.textReverse() ;
  wcout << gs.gstr() << endl ;
  
  OUTPUT (correct except punctuation) : האם אתה מוכן לארוחת צהריים?
  
  gs = Lunch ;
  gs.textReverse( true ) ;
  wcout << gs.gstr() << endl ;
  
  OUTPUT (correct): ?האם אתה מוכן לארוחת צהריים
  
  // When the 'punct' flag is set, both leading and trailing punctuation 
  // are identified.
  // Questions in Spanish use a leading inverted question mark (U+00BF), 
  // and a trailing ASCII question mark (U+003F).
  // Reverse the internal text but do not reverse the terminal punctuation.
  gs = "¿ozreumla le arap atsil sátsE?" ;
  gs.textReverse( true ) ;
  wcout << gs.gstr() << endl ;
  
  OUTPUT : ¿Estás lista para el almuerzo?
  
   = = = = =
   
  // Reverse multi-line text (paragraph formatting).
  // Ordinary ASCII text is used for this example 
  // to demonstrate the reversal.
  // The example outputs to an NcDialog window referenced by NcDialog *dp
  const char* Vaccine = "Have you received your covid-19 vaccination yet?\n
                        "Protect yourself and others,\n"
                        "get your vaccination today!" ;
  gs = Vaccine ;
  // Write unmodified text as LTR data:
  dp->WriteParagraph ( 1, 1, gs, nc.grR, true, false ) ;
  
  OUTPUT: Have you received your covid-19 vaccination yet?
          Protect yourself and others,
          get your vaccination today!
  
  // Reverse the data, without punctuation processing or 
  // right-justification. (Note: all parameters are optional, 
  // but are shown here for clarity.)
  gs.textReverse( false, true, false ) ;
  
  // Write reversed text as LTR data:
  dp->WriteParagraph ( 1, 1, gs, nc.grR, true, false ) ;
  
  OUTPUT: ?tey noitaniccav 91-divoc ruoy deviecer uoy evaH
          ,srehto dna flesruoy tcetorP
          !yadot noitaniccav ruoy teg
  
  // Write the same data as RTL (note the X origin of 48):
  dp->WriteParagraph ( 1, 48, gs, nc.grR, true, true ) ;
  OUTPUT: ?tey noitaniccav 91-divoc ruoy deviecer uoy evaH
                              ,srehto dna flesruoy tcetorP
                               !yadot noitaniccav ruoy teg
  
  // Reload the source data and reverse it without punctuation processing,
  // but WITH right-justification padding.
  gs = Vaccine ;
  gs.textReverse( false, true, true ) ;
  
  // Write reversed text as LTR data.
  // Note that the padding character is ASCII space ' ',
  // however the '-' character is used here to show the padding position.
  dp->WriteParagraph ( 1, 1, gs, nc.grR, true, false ) ;
  
  OUTPUT: ?tey noitaniccav 91-divoc ruoy deviecer uoy evaH
          --------------------,srehto dna flesruoy tcetorP
          ---------------------!yadot noitaniccav ruoy teg
  
  // Write the same data as RTL (note the X origin of 48):
  dp->WriteParagraph ( 1, 48, gs, nc.grR, true, true ) ;
  
  OUTPUT: ?tey noitaniccav 91-divoc ruoy deviecer uoy evaH
          --------------------,srehto dna flesruoy tcetorP
          ---------------------!yadot noitaniccav ruoy teg
  
  // Combine RTL text with numeric (LTR) data.
  // Create an ASCII numeric time string.
  // Reverse the numeric string.
  // Insert a Hebrew label: "The current time is: "
  const wchar_t *timeLabel = L"השעה הנוכחית היא: " ; //(displayed incorrectly)
  short hours = 12, minutes = 32, seconds = 45 ;
  gs.compose( "%02hd:%02hd:%02hd", &hours, &minutes, &seconds ) ;
  gs.textReverse( false, true, false ) ;
  gs.insert( timeLabel ) ;
  
  // Write the data as RTL (note the X origin of 26):
  dp->WriteParagraph ( 1, 26, gs, nc.grR, true, true ) ;
  
  OUTPUT:
     12:32:45 :השעה הנוכחית היא
  
  

  Technical Note On Punctuation

  Determining which characters are and are not punctuation is locale specific (see the 'ispunct()' C-language function).
  Rather than rely on the locale used by the application calling this method, we test against a list of the most common punctuation characters used in modern languages. If a punctuation character used by your application is not recognized as punctuation, please send us a note including the Unicode codepoint and we will add it to the list.

Comparisons

• short compare ( const char* uStr, bool casesen = true,
                  short length = gsMAXCHARS, short offset = 0 ) const ;
  
• short compare ( const wchar_t* wStr, bool casesen = true,
                  short length = gsMAXCHARS, short offset = 0 ) const ;

    Input  :
       uStr     : (UTF-8 string) to be compared
         OR
       wStr     : (wchar_t string) to be compared
       casesen  : (optional, 'true' by default)
                  if 'true' perform case-sensitive comparison
                  if 'false' perform case-insensitive comparison
       length   : (optional, gsMAXCHARS by default. i.e. compare to end)
                  maximum number of characters to compare
       offset   : (optional, ZERO by default)
                  If specified, equals the character offset into the
                  gString character array at which to begin comparison.
  
    Returns: 
       return value uses the rules of the 'wcsncmp' (or 'wcsncasecmp') 
       library function (see string.h):
         ZERO, text data are identical
       > ZERO, first differing char of gString object is numerically larger.
       < ZERO, first differing char of gString object is numerically smaller.
  

  Compares the text content of the gString object with the specified text.

  The comparison is performed against the gString object’s wchar_t character array. The relationship between upper-case and lower-case characters is locale dependent.

• short compare ( const gString& gs, bool casesen = true ) const ;
  

    Input  :
       gs       : (by reference) object whose text is to be compared
       casesen  : (optional, 'true' by default)
                  if 'true' perform case-sensitive comparison
                  if 'false' perform case-insensitive comparison
  
    Returns:
       return value uses the rules of the 'wcsncmp' (or 'wcsncasecmp') 
       library function (see string.h):
         ZERO, text data are identical
       > ZERO, first differing char of gString object is numerically larger.
       < ZERO, first differing char of gString object is numerically smaller.
  

  Compares the text content of two gString objects.

  The comparison is performed against the gString objects’ wchar_t character arrays. The relationship between upper-case and lower-case characters is locale dependent.

  
  
  
• bool operator == ( const gString& gs2 ) const ;

    Input  :
       gs2   : (by reference)
               gString object containing string to be compared
    Returns:
       'true' if the strings are identical, else 'false'
  

  Comparison operator: Compares the text content of two gString objects.

  The comparison is performed against the wchar_t character arrays of the two objects. The comparison is is case-sensitive.

  
  
  
• bool operator != ( const gString& gs2 ) const ;

    Input  :
       gs2   : (by reference)
               gString object containing string to be compared
    Returns:
       'true' if the strings are different, else 'false'
  

  Comparison operator: Compares the text content of two gString objects.

  The comparison is performed against the wchar_t character arrays of the two objects. The comparison is is case-sensitive.

  
  
  
• short find ( const char* src, short offset=0,
               bool casesen=false, short maxcmp= -1 ) const ;
• short find ( const wchar_t* src, short offset=0,
               bool casesen=false, short maxcmp= -1 ) const ;
• short find ( const gString& src, short offset=0,
               bool casesen=false, short maxcmp= -1 ) const ;
• short find ( const wchar_t src, short offset=0,
               bool casesen=false ) const ;

    Input  :
       src    : source data to be matched, one of the following:
                -- pointer to a UTF-8 string (max length==gsMAXBYTES)
                -- pointer to a wchar_t string (max length==gsMAXCHARS)
                -- a gString object containing the source (by reference)
                -- a single, wchar_t character
       offset : (optional, ZERO by default)
                character index at which to begin search
                -- if out-of-range, then same as if not specified
       casesen: (optional, 'false' by default)
                if 'false', then scan IS NOT case sensitive
                if 'true, then scan IS case sensitive
                The way upper/lowercase are related is locale dependent;
       maxcmp : (optional, (-1) by default)
                -- if not specified, then scan for a match of all
                   characters in 'src' (not including null terminator)
                -- if specified, then scan for a match of only the first
                   'maxcmp' characters of 'src'
                -- if out-of-range, then same as if not specified
    Returns:
       index of matching substring or (-1) if no match found
       Note: This is the wchar_t character index, NOT a byte index
  

  Scan the data for a matching substring and if found, return the index at which the first substring match begins.

  Actual comparison is always performed against the ’wide’ character array using wcsncasecmp (or wcsncmp). Null terminator character IS NOT included in the comparison. These comparisons ARE locale dependent.

  
  
• short findlast ( const char* src, bool casesen=false ) const ;
• short findlast ( const wchar_t* src, bool casesen=false ) const ;
• short findlast ( const gString& src, bool casesen=false ) const ;
• short findlast ( const wchar_t src, bool casesen=false ) const ;

    Input  :
       src    : source data to be matched, one of the following:
                -- pointer to a UTF-8 string (max length==gsMAXBYTES)
                -- pointer to a wchar_t string (max length==gsMAXCHARS)
                -- a gString object containing the source (by reference)
                -- a single, wchar_t character
       casesen: (optional, 'false' by default)
                if 'false', then scan IS NOT case sensitive
                if 'true, then scan IS case sensitive
                The way upper/lowercase are related is locale dependent;
  
    Returns:
       index of last matching substring or (-1) if no match found
       Note: This is the wchar_t character index, NOT a byte index
  

  Scan the data for the last occurance of the matching substring and if found, return the index at which the substring match occurs.

  Actual comparison is always performed against the ’wide’ character array using wcsncasecmp (or wcsncmp). Null terminator character IS NOT included in the comparison. These comparisons ARE locale dependent.

  
  
• short after ( const char* src, short offset=0,
                bool casesen=false ) const ;
• short after ( const wchar_t* src, short offset=0,
                bool casesen=false ) const ;
• short after ( const gString& src, short offset=0,
                bool casesen=false ) const ;

    Input  :
       src    : source data to be matched, one of the following:
                -- pointer to a UTF-8 string (max length==gsMAXBYTES)
                -- pointer to a wchar_t string (max length==gsMAXCHARS)
                -- a gString object containing the source (by reference)
       offset : (optional, ZERO by default)
                character index at which to begin search
                -- if out-of-range, then same as if not specified
       casesen: (optional, 'false' by default)
                if 'false', then scan IS NOT case sensitive
                if 'true, then scan IS case sensitive
                The way upper/lowercase are related is locale dependent;
    Returns:
       index of the character which follows the matching substring
         or (-1) if no match found
       Note: This is the wchar_t character index, NOT a byte index
  

  This method is very similar to the ’find()’ method above, but instead of returning the index to the beginning of the substring, returns the index of the character which FOLLOWS the substring.

  
  
• short findx ( wchar_t srcChar = L' ', short offset=0 ) const ;

    Input  :
       srcChar: (optional, L' ' by default) character to be skipped over
       offset : (optional, ZERO by default)
                if specified, equals the character offset into the 
                character array at which to begin the scan.
    Returns:
       a) If successful, returns the index of first character which 
          DOES NOT match specified character.
       b) If the scan finds no character which is different from the 
          specified character, OR if 'offset' is out of range, OR if the 
          specified character is the null character, the return value 
          indexes the null terminator of the array.
       Note: This is the wchar_t character index, NOT a byte index
  

  Scan the text and locate the first character which DOES NOT match the specified character.

  This method is used primarily to scan past the end of a sequence of space (' ') characters (0x0020), but may be used to skip over any sequence of a single, repeated character. Note that the character specified must be a ‘wide’ (wchar_t) character.

  See also the ’scan’ method below which scans to the first non-whitespace character.

  
  
• short scan ( short offset=0 ) const ;

    Input  :
       offset : (optional, ZERO by default)
                if specified, equals the character offset into the 
                character array at which to begin the scan.
    Returns:
       a) If successful, returns the index of first non-whitespace 
          character
       b) If the scan finds no non-whitespace character OR if 'offset' 
          is out of range, the return value indexes the null terminator 
          of the array.
       Note: This is the wchar_t character index, NOT a byte index.
  

  Scans the text array and returns the index of the first non-whitespace character found.

  Whitespace characters are defined as:
  0x0020 single-column ASCII space
  0x3000 two-column CJK space
  0x0A linefeed character
  0x0D carriage-return character
  0x09 horizontal-tab character
  0x0B vertical-tab character
  0x0C formfeed character
  

Examples

gString str1( "Toys for Tots" ) ;
gString str2( "The Tin Drum" ) ;

// compare with UTF-8 string
short result = str1.compare( "Toys for Tots" ) ;

// compare with wchar_t string
short result = str2.compare( L"The Tin Drum" ) ;

// compare gString objects
if ( str1 == str2 ) { /* do stuff */ }
if ( str1 != str2 ) { /* do stuff */ }


gString gs( L"Tiny Tim had a titillating tour of Times Square." ) ;

// find first instance of substring "tim" (not case sensitive)
short tIndex = gs.find( "tim" ) ;
wcout << &gs.gstr()[tIndex] << endl ;
 - - -> Tim had a titillating tour of Times Square.

// find the next instance of "tim"
gString gsSub( "tim" ) ;      // search string in a gString object
tIndex = gs.find( gsSub, tIndex + 1 ) ;
wcout << &gs.gstr()[tIndex] << endl ;
 - - -> Times Square.

// find first instance of substring "ti" (case sensitive)
tIndex = gs.find( L"ti", 0, true ) ;
wcout << &gs.gstr()[tIndex] << endl ;
 - - -> titillating tour of Times Square.

// match the first three characters of the search string
tIndex = gs.find( L"squirrel", 0, false, 3 ) ;
wcout << &gs.gstr()[tIndex] << endl ;
 - - -> Square.

// find first instance of L'R' (not case sensitive)
tIndex = gs.find( L'R' ) ;
wcout << &gs.gstr()[tIndex] << endl ;
 - - -> r of Times Square.

// extract the filename from path/filename string
gString gs( "/home/sam/SoftwareDesign/NcDialog/Dialog1/gString.hpp" ) ;
if ( (tIndex = gs.findlast( L'/' )) >= 0 )
   wcout << &gs.gstr()[tIndex + 1] << endl ;
 - - -> gString.hpp

// insert text after first instance of substring
gString gs( "I think that a parrot would be an ideal pet." ) ;
short pIndex = gs.after( L"would" ) ;
gs.insert( " NOT", pIndex ) ;
 - - -> I think that a parrot would NOT be an ideal pet.

For more examples of using gString-class methods, please refer to Test #6 of the ’Dialogw’ test application.

Extract Formatted Data

• short gscanf ( const wchar_t* fmt, ... ) const ;
  
• short gscanf ( const char* fmt, ... ) const ;

    Input  :
       fmt  : a format specification template in the style of swscanf()
              or sscanf() and related C/C++ functions
              Template may be either a const char* OR a const wchar_t*
  
       ...  : optional arguments
              Each optional argument is a POINTER to (address of) the
              variable to receive the formatted data.
              - Important Note: There must be AT LEAST as many optional
                arguments as the number of format specifiers defined in
                the formatting template. Excess arguments will be
                ignored; however, too few arguments will return an
                error condition. (see below)
  
    Returns: 
       number of items captured and converted
       returns 0 if:
         a) number of format specifications in 'fmt' > gsFormMAXARGS
         b) number of format specifications in 'fmt' > number of
            optional arguments (pointers to target variables) provided
  

  Scan the text data contained in the gString object and extract data according to the specified formatting template.
  (This is an implementation of the standard C-library ’swscanf’ function.)

  The formatting template may be either a 'const wchar_t*' as in a call to 'swscanf', or a 'const char*' as in a call to 'sscanf'.

  The formatting template may contain between zero(0) and gsFormMAXARGS format specifiers.

  The optional arguments are pointers to the target variables which will receive the formatted data.

  As with 'swscanf', the number of optional arguments must be equal to or greater than the number of format specifiers:
  (%d, %63s, %X %lld, %24lls, %[, etc.).
  Excess arguments will be ignored; however, unlike the 'swscanf' function, 'gscanf' counts the number of format specifiers and optional arguments, and if there are too few arguments, the scan will be aborted to avoid an application crash due to memory-access violation. (You’re welcome :-)

  
  
  
• short gscanf ( short offset, const wchar_t* fmt, ... ) const ;
  
• short gscanf ( short offset, const char* fmt, ... ) const ;

    Input  :
       offset: wide-character offset at which to begin the scan
               Important Note: This IS NOT a byte offset.
               If offset < 0 || offset > length of data, offset will
               be silently set to 0.
  
       fmt   : a format specification template in the style of swscanf()
               or sscanf() and related C/C++ functions
               Template may be either a const char* OR a const wchar_t*
  
       ...   : optional arguments
               Each optional argument is a POINTER to (address of) the
               variable to receive the formatted data.
               - Important Note: There must be AT LEAST as many optional
                 arguments as the number of format specifiers defined in
                 the formatting template. Excess arguments will be
                 ignored; however, too few arguments will return an
                 error condition. (see below)
  
    Returns: 
       number of items captured and converted
       returns 0 if:
         a) number of format specifications in 'fmt' > gsFormMAXARGS
         b) number of format specifications in 'fmt' > number of
            optional arguments (pointers to target variables) provided
  

  This is the same method as described above except that the scan of the data begins at the specified character offset.

  
  

  Examples

  short sval1, sval2, sval3, sval4 ;
  int   ival ;
  long long int llval ;
  double dval ;
  char   str1[64], str2[16], str3[16], ch1 ;
  gString gs( "17 % 18 21 22 48A2B 720451 24.325 A country song "
              "is three chords and the truth. - Willie Nelson" ) ;
  short cnt = 
     gs.gscanf( L"%hd %% %hd %hd %hd %X %lld %lf %63[^-] %c %16s %16s", 
                &sval1, &sval2, &sval3, &sval4, &ival, &llval, 
                &dval, str1, &ch1, str2, str3 ) ;
  
  gString gsOut( "items    : %hd\n"
                 "numeric  : %hd  %hd  %hd  %hd  0x%04X  %lld  %4.6lf\n"
                 "text data: \"%s\" %c %s %s\n",
                 &cnt, &sval1, &sval2, &sval3, &sval4, &ival, &llval, &dval, 
                 str1, &ch1, str2, str3 ) ;
  dp->WriteParagraph ( 1, 1, gsOut, dColor ) ;
  
  This yields:
  items    : 11
  numeric  : 17  18  21  22  0x48A2B  720451  24.325000
  text data: "A country song is three chords and the truth. " - Willie Nelson
  
  A working example may be found in the NcDialog API package, 
  (Dialogw test application, Test #6).
  
   - - - - -
  
  To begin the scan from a particular offset into the text, the unneeded 
  initial data may either be scanned into a throw-away buffer or the 
  scan offset may be specified directly. For example, to discard the 
  first sixteen(16) characters:
  
  wchar_t junk[gsMAXCHARS] ;
  gs = "Useless garbage: 17 21 34" ;
  
  gs.gscanf( L"%16C %hd %hd %hd", junk, &sval1, &svan2, &sval3 ) ;
    _or_
  gs.gscanf ( 16, L"%hd %hd %hd", &sval1, &svan2, &sval3 ) ;
  
  

  Programmer’s Note: It is good practice to specify a maximum length for all scanned strings in order to avoid overrun of the target buffer. THIS: %64s %128lls %256S %32[a-z] NOT THIS: %s %lls %S %[a-z]

Statistical Info

• short gString::gschars ( void ) const ;

    Input  :
       none
    Returns:
       number of characters in the string
  

  Returns the number of characters in the string including the null terminator.

  
  
  
• short utfbytes ( void ) const ;

    Input  :
       none
    Returns:
       number of bytes in UTF-8 string
  

  Returns the number of bytes in the UTF-8-encoded string including the null terminator.

  
  
  
• short gscols ( void ) const ;

   Input  :
      none
   Returns:
      number of columns needed to display the data
  

  Returns the number of columns required to display the string.

  
  
  
• const short* gscols ( short& charCount ) const ;

    Input  :
       charCount : (by reference, initial value ignored)
                   on return, contains number of characters in 
                   the string including the null terminator.
    Returns:
       pointer to number of columns needed for display of each character
  

  Returns a pointer to an array of column counts, one for each character of the text data. Note that number of array elements equals number of characters (plus meta-characters, if any).

  Example

  This example is from the FileMangler utility. It trims the head of 
  the provided path/filename string to fit within a dialog window.
  
  void FmConfig::ecoPathFit ( gString& gsPath, short colsAvail )
  {
     if ( (gsPath.gscols()) > colsAvail )
     {
        gString gst = gsPath ;
        short width = gst.gscols(),
              offset = ZERO,
              charCount ;
        const short* colArray = gst.gscols( charCount ) ;
  
        while ( width > (colsAvail - 3) )
           width -= colArray[offset++] ;
        gsPath.compose( L"...%S", &gst.gstr()[offset] ) ;
     }
  }  //* End ecoPathFit() *
  

  
  
  
• bool isASCII ( void ) ;

    Input  :
       none
    Returns:
       'true' if data are pure, 7-bit ASCII, else 'false'
  

  Scan the data to determine whether it is pure, 7-bit ASCII.

gString Miscellaneous

• void gString::clear ( void ) ;

    Input  :
       none
    Returns:
       nothing
  

  Reset contents to an empty string i.e. "". The data will consist of a single, NULLCHAR character. The character and byte counts are set to 1 (one), and the column count is zero.

  
  
  
• const char* Get_gString_Version ( void ) const ;

    Input  :
       none
    Returns:
       pointer to version string
  

  Return a pointer to gString class version number string.

  
  
  
• void gString::dbMsg ( gString& gsmsg ) ;

    Input  :
       gsmsg : (caller's object, by reference)
               receives most recent debug message
    Returns:
       nothing
  

  FOR DEBUGGING ONLY! Application can retrieve most recent debug message.
  Note: This method is visible only if the ENABLE_GS_DEBUG flag is set in gString.hpp.

gString Examples

The NcDialog API test application ’Dialogw’ contains extensive examples of gString usage, including working copies of the examples used in this chapter.
The other NcDialog API test applications also use gString in various ways.

Here, we show just a sample of some basic uses for the gString class.

1. Convert a UTF-8 (8-bit) character string to a wchar_t (32-bit) character string.

   const char* some_UTF-8_data = "I want to buy an hamburger." ;
   wchar_t some_wide_data[gsMAXCHARS] ;
   
   gString gs( some_UTF-8_data ) ;
   gs.copy( some_wide_data, gsMAXCHARS ) ;
   

2. Convert a wchar_t (32-bit) character string to a UTF-8 (8-bit) character string.

   const wchar_t* some_wide_data = L"I want to buy an hamburger." ;
   char some_UTF-8_data[gsMAXBYTES] ;
   
   gString gs( some_wide_data ) ;
   gs.copy( some_UTF-8_data, gsMAXBYTES ) ;
   

3. Concatenate strings.

   const char* Head = "Where" ;
   const wchar_t* Tail = L"is Carmen Sandiego?" ;
   gString gs( L" in the world " ) ;
   gs.insert( Head, ZERO ) ;
   gs.append( Tail ) ;
   wcout << gs << endl ;
    - - ->  Where in the world is Carmen Sandiego?
   

4. Create formatted string data.

   const char* utf8String = "We present" ;
   const wchar_t* wideString = L"for your enjoyment:" ;
   const char utf8Char = 'W' ;
   const wchar_t wideChar = L'C' ;
   short int ways = 100 ;
   double dish = 17.57 ;
   gString gs ;
   
   gs.compose( "%s %S %hd %cays to %Cook %Chicken,\n"
               "and %.2lf side dishes and beverages!",
               utf8String,
               wideString,
               &ways,
               &utf8Char,
               &wideChar, &wideChar,
               &dish ) ;
   
   wcout << gs << endl ;
    - - ->  We present for your enjoyment: 100 Ways to Cook Chicken,
            and 17.57 side dishes and beverages!
   

   Important Note: All parameters are pointers to the data: For strings (and pointers), the address is the name of the variable. For all other data types, including single characters, use the address-of ('&') operator.

5. Count display columns to make data fit the window.

   This is a formatting method taken from the ’Dialogx’ test application. It breaks a text stream into lines which fit within the dianostic window. It’s not speedy (or particularly smart), but it demonstrates the use of ’gString’ to calculate the space needed to display text data and then formatting the data to fit the space.

   //*  FormatOutput   *
   //* Input  : gsOut     : semi-formatted source data
   //*          wpos      : start position for display
   //*          lineCount : maximum display lines before truncation
   //* Returns: nothing
   
   void dXClip::FormatOutput ( const gString& gsOut, 
                               winPos& wpos, short lineCount )
   {
      short tWidth = (ddCOLS - 2),        // inside width of target window
            maxWidth = tWidth * lineCount,// max columns for message
            tLines = ZERO ;               // loop counter
   
      gString gsw( gsOut.gstr() ), gso ;
      if ( gsw.gscols() > maxWidth )
      { // truncate the string if necessary
         gsw.limitCols ( maxWidth - 3 ) ;
         gsw.append( L"..." ) ;
      }
      do
      {  // break the source into convenient widths
         gso = gsw ;
         gso.limitCols( tWidth ) ;
         gso.append( L'\n' ) ;
         gsw.shiftCols( -tWidth ) ;
         this->dpd->ClearLine ( wpos.ypos ) ; // clear target display line
         wpos = this->dpd->WriteParagraph ( wpos, gso, 
                                            dxPtr->dColor, true ) ;
      }
      while ( ++tLines <= lineCount && gsw.gschars() > 1 ) ;
   
   }  //* End FormatOutput() *
   

   The example above is just a simple one. To see it in action, please refer to the ’Dialogw’ NcDialog API Test Application, test seven (7). For a more sophisticated example, see the ’DialogTextbox::mlFmtDisplay’ automatic word-wrapping method in the NcDialog API source code.

GNU General Public License

Preamble

The GNU General Public License is a free, copyleft license for software and other kinds of works.

The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program—to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.

To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.

Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it.

For the developers’ and authors’ protection, the GPL clearly explains that there is no warranty for this free software. For both users’ and authors’ sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.

Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users’ freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users.

Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free.

The precise terms and conditions for copying, distribution and modification follow.

TERMS AND CONDITIONS

0. Definitions.

   “This License” refers to version 3 of the GNU General Public License.

   “Copyright” also means copyright-like laws that apply to other kinds of works, such as semiconductor masks.

   “The Program” refers to any copyrightable work licensed under this License. Each licensee is addressed as “you”. “Licensees” and “recipients” may be individuals or organizations.

   To “modify” a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a “modified version” of the earlier work or a work “based on” the earlier work.

   A “covered work” means either the unmodified Program or a work based on the Program.

   To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.

   To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying.

   An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion.

1. Source Code.

   The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-source form of a work.

   A “Standard Interface” means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language.

   The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it.

   The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work’s System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work.

   The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source.

   The Corresponding Source for a work in source code form is that same work.

2. Basic Permissions.

   All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law.

   You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you.

   Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary.

3. Protecting Users’ Legal Rights From Anti-Circumvention Law.

   No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures.

   When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work’s users, your or third parties’ legal rights to forbid circumvention of technological measures.

4. Conveying Verbatim Copies.

   You may convey verbatim copies of the Program’s source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.

   You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.

5. Conveying Modified Source Versions.

   You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:

   1. The work must carry prominent notices stating that you modified it, and giving a relevant date.
   2. The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to “keep intact all notices”.
   3. You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.
   4. If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.

   A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation’s users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.

6. Conveying Non-Source Forms.

   You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:

   1. Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.
   2. Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.
   3. Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.
   4. Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.
   5. Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.

   A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.

   A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.

   “Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.

   If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).

   The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.

   Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.

7. Additional Terms.

   “Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.

   When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission.

   Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:

   1. Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or
   2. Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or
   3. Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or
   4. Limiting the use for publicity purposes of names of licensors or authors of the material; or
   5. Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or
   6. Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors.

   All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying.

   If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms.

   Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way.

8. Termination.

   You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).

   However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

   Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

   Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10.

9. Acceptance Not Required for Having Copies.

   You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.

10. Automatic Licensing of Downstream Recipients.

    Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License.

    An “entity transaction” is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party’s predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts.

    You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.

11. Patents.

    A “contributor” is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor’s “contributor version”.

    A contributor’s “essential patent claims” are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, “control” includes the right to grant patent sublicenses in a manner consistent with the requirements of this License.

    Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor’s essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.

    In the following three paragraphs, a “patent license” is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To “grant” such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.

    If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. “Knowingly relying” means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient’s use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid.

    If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it.

    A patent license is “discriminatory” if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.

    Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law.

12. No Surrender of Others’ Freedom.

    If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.

13. Use with the GNU Affero General Public License.

    Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.

14. Revised Versions of this License.

    The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.

    Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation.

    If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Program.

    Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version.

15. Disclaimer of Warranty.

    THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

16. Limitation of Liability.

    IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16.

    If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.

Also add information on how to contact you by electronic and paper mail.

If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:

The hypothetical commands ‘show w’ and ‘show c’ should show the appropriate parts of the General Public License. Of course, your program’s commands might be different; for a GUI interface, you would use an “about box”.

You should also get your employer (if you work as a programmer) or school, if any, to sign a “copyright disclaimer” for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see https://www.gnu.org/licenses/.

The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read https://www.gnu.org/licenses/why-not-lgpl.html.

GNU Free Documentation License

0. PREAMBLE

   The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

   This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

   We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.

1. APPLICABILITY AND DEFINITIONS

   This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

   A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

   A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

   The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.

   The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

   A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.

   Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.

   The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.

   The “publisher” means any person or entity that distributes copies of the Document to the public.

   A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.

   The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.

2. VERBATIM COPYING

   You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.

   You may also lend copies, under the same conditions stated above, and you may publicly display copies.

3. COPYING IN QUANTITY

   If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

   If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

   If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

   It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.

4. MODIFICATIONS

   You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

   1. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.
   2. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.
   3. State on the Title page the name of the publisher of the Modified Version, as the publisher.
   4. Preserve all the copyright notices of the Document.
   5. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
   6. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
   7. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice.
   8. Include an unaltered copy of this License.
   9. Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.
   10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.
   11. For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.
   12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.
   13. Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version.
   14. Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section.
   15. Preserve any Warranty Disclaimers.

   If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

   You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

   You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

   The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

5. COMBINING DOCUMENTS

   You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

   The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

   In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”

6. COLLECTIONS OF DOCUMENTS

   You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

   You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

7. AGGREGATION WITH INDEPENDENT WORKS

   A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

   If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

8. TRANSLATION

   Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

   If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

9. TERMINATION

   You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

   However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

   Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

   Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

10. FUTURE REVISIONS OF THIS LICENSE

    The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/licenses/.

    Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

11. RELICENSING

    “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

    “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

    “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

    An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

    The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.