cmdline(n)            Command line and option processing            cmdline(n)



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NAME
       cmdline - Procedures to process command lines and options.

SYNOPSIS
       package require Tcl  8.2

       package require cmdline  ?1.3.2?

       ::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
              specified.  This also generates an error message that lists the
              allowed flags if an incorrect flag is specified. The optional
              usage-argument 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
              argument.  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 ...\noptions:"
                      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                              1.3.2                          cmdline(n)
