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NAME
	gpp - Bash-based preprocessor for anything

	gpp: General Preprocessor

SYNOPSIS
	gpp [OPTION]...

DESCRIPTION
	gpp lets a developer embed directives written in GNU
	Bash into any text document. These directives are used
	to automate the writting of parts of the document.

	The preprocessing directives start with a symbol
	(or text string) specified by the developer. By default
	this symbol is @ (at).

	Any line starting with @< (where @ is the selected
	symbol for preprocessing directives) or @>, or is
	between a line starting with @< and a line starting
	with @>, is parsed as a line, written in Bash, that
	is executed during preprocessing.
	A @< line must have an associated @> line somewhere
	after it, all lines between them are parsed as
	preprocessing directives. A @> does however not need
	an associated @< line somewhere before it, making
	@> suitable for single line directives.

	Preprocessing directives can also be inline. For this,
	use @(COMMAND) where COMMAND is the Bash code to run.
	Additionally, gpp supports variable substitution.
	@{VARIABLE} will be replaces by the value if the
	variable (possibility environment variable) VARIABLE.
	gpp supports all modifiers thats Bash supports. For
	example, if you want the value to be included but
	uppercase you can write @{VARIABLE^^}, or @{VARIABLE,,}
	for lowercase.

	Everything that is not preprocessing directives is
	threaded as echo(1):ed lines.

OPTIONS
	-s, --symbol SYMBOL
		Set the prefix symbol for preprocessor directives.
		Defaults to @.

	-e, --encoding ENCODING
		Specifies the encoding of the file.

	-n, --iterations N
		Process the file recursively N times. Defaults to 1 time.

	-u, --unshebang
		Clear the shebang line, remove it if this flag
		is used twice. If used twice, an empty line
		will be inserted after the new first line.

	-i, --input FILE
		Select file to process. Defaults to /dev/stdin.

	-o, --output FILE
		Select output file. Defaults to /dev/stdout.

	-f, --file FILE
		Equivalent to -i FILE -o FILE.

	-D, --export NAME=VALUE
		Set the environment variable NAME to hold
		the value VALUE.

	-D, --export NAME
		Set the environment variable NAME to hold
		the value 1.

	-v, --version
		Print program name and version and exit.

	-c, --copying
		Print copyright notice and exit.

	Short options must be joined. The value of a flag must
	be in a separate argument from the flag itself.

RATIONALE
	Programmers need more automation when we write software
	and documentation. An unrestricted preprocessor lets
	you automate just about anything. Of course, it can be
	used for anything, must just writing software and
	documentation. Preprocessing can be used for more than
	automation, it can also be used to increase the flexibility
	of the work.

	C is one of the few languages that includes a preprocessor,
	some times it is not enough; and all languages need
	preprocessors.

SEE ALSO
	bash(1), jpp(1), cpp(1), env(1)

	Full documentation available locally via: info '(gpp)'