cmdline(3tcl)						Command line and option processing					     cmdline(3tcl)

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NAME

       cmdline - Procedures to process command lines and options.

SYNOPSIS

       package require Tcl  8.2

       package require cmdline	?1.3.3?

       ::cmdline::getopt argvVar optstring optVar valVar

       ::cmdline::getKnownOpt argvVar optstring optVar valVar

       ::cmdline::getoptions arglistVar optlist ?usage?

       ::cmdline::getKnownOptions arglistVar optlist ?usage?

       ::cmdline::usage optlist ?usage?

       ::cmdline::getfiles patterns quiet

       ::cmdline::getArgv0

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DESCRIPTION

       This package provides commands to parse command lines and options.

::ARGV HANDLING
       One  of	the  most common variables this package will be used with is ::argv, which holds the command line of the current application. This
       variable has a companion ::argc which is initialized to the number of elements in ::argv at the beginning of the application.

       The commands in this package will not modify the ::argc companion when called with ::argv. Keeping the value consistent, if such is desired
       or required, is the responsibility of the caller.

API

       ::cmdline::getopt argvVar optstring optVar valVar
	      This command works in a fashion like the standard C based getopt function.  Given an option string and a pointer to an array of args
	      this command will process the first argument and return info on how to proceed. The command returns 1 if an option was found,  0	if
	      no more options were found, and -1 if an error occurred.

	      argvVar contains the name of the list of arguments to process. If options are found the list is modified and the processed arguments
	      are removed from the start of the list.

	      optstring contains a list of command options that the application will accept.  If the option ends in ".arg" the	command  will  use
	      the next argument as an argument to the option.  Otherwise the option is a boolean that is set to 1 if present.

	      optVar refers to the variable the command will store the found option into (without the leading '-' and without the .arg extension).

	      valVar  refers  to the variable to store either the value for the specified option into upon success or an error message in the case
	      of failure. The stored value comes from the command line for .arg options, otherwise the value is 1.

       ::cmdline::getKnownOpt argvVar optstring optVar valVar
	      Like ::cmdline::getopt, but ignores any unknown options in the input.

       ::cmdline::getoptions arglistVar optlist ?usage?
	      Processes the set of command line options found in the list variable named by arglistVar and fills in defaults for those not  speci-
	      fied.  This also generates an error message that lists the allowed flags if an incorrect flag is specified. The optional usage-argu-
	      ment contains a string to include in front of the generated message. If not present it defaults to "options:".

	      optlist contains a list of lists where each element specifies an option in the form: flag default comment.

	      If flag ends in ".arg" then the value is taken from the command line. Otherwise it is a boolean and appears in the result if present
	      on the command line. If flag ends in ".secret", it will not be displayed in the usage.

	      The options -?, -help, and -- are implicitly understood. The first two abort option processing and force the generation of the usage
	      message, whereas the the last aborts option processing without an error, leaving all arguments coming after for regular  processing,
	      even if starting with a dash.

	      The result of the command is a dictionary mapping all options to their values, be they user-specified or defaults.

       ::cmdline::getKnownOptions arglistVar optlist ?usage?
	      Like ::cmdline::getoptions, but ignores any unknown options in the input.

       ::cmdline::usage optlist ?usage?
	      Generates  and  returns an error message that lists the allowed flags. optlist is defined as for ::cmdline::getoptions. The optional
	      usage-argument contains a string to include in front of the generated message. If not present it defaults to "options:".

       ::cmdline::getfiles patterns quiet
	      Given a list of file patterns this command computes the set of valid files.  On windows, file globbing is performed  on  each  argu-
	      ment.   On  Unix, only file existence is tested.	If a file argument produces no valid files, a warning is optionally generated (set
	      quiet to true).

	      This code also uses the full path for each file.	If not given it prepends the current  working  directory  to  the  filename.  This
	      ensures that these files will never conflict with files in a wrapped zip file. The last sentence refers to the pro-tools.

       ::cmdline::getArgv0
	      This  command  returns  the  "sanitized" version of argv0.  It will strip off the leading path and removes the extension ".bin". The
	      latter is used by the pro-apps because they must be wrapped by a shell script.

EXAMPLES

		      set options {
			  {a	      "set the atime only"}
			  {m	      "set the mtime only"}
			  {c	      "do not create non-existent files"}
			  {r.arg  ""  "use time from ref_file"}
			  {t.arg  -1  "use specified time"}
		      }
		      set usage ": MyCommandName [options] filename ...
options:"
		      array set params [::cmdline::getoptions argv $options $usage]

		      if {  $params(a) } { set set_atime "true" }
		      set has_t [expr {$params(t) != -1}]
		      set has_r [expr {[string length $params(r)] > 0}]
		      if {$has_t && $has_r} {
			  return -code error "Cannot specify both -r and -t"
		      } elseif {$has_t} {
		    ...
		      }

       This example, taken (and slightly modified) from the package fileutil, shows how to use cmdline.  First, a list of options is created, then
       the  'args'  list  is passed to cmdline for processing.	Subsequently, different options are checked to see if they have been passed to the
       script, and what their value is.

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain bugs and other problems.  Please report such in the category  cmdline
       of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883].  Please also report any ideas for enhancements you may have for
       either package and/or documentation.

KEYWORDS

       argument processing, argv, argv0, cmdline processing, command line processing

CATEGORY

       Programming tools

cmdline 							       1.3.3							     cmdline(3tcl)