** Summary ** This global variable is provided by [tclsh] and [wish] mainline code (and '''NOT''' the tcl or tk libraries). ** Description ** `$argv` contains the arguments the app was called with as a list, similar to C's argv, but without the app name itself, which is stored in `$::[argv0]`. While ''[argc]'' exists, we don't really need it since we can always determine [[llength $argv]]. An example of making use of this variable is: ====== #! /usr/local/bin/tclsh if { $::argc > 0 } { set i 1 foreach arg $::argv { puts "argument $i is $arg" incr i } } else { puts "no command line argument passed" } ====== [DGP]: It is true that we do not need ''::argc'', but '''tclsh''' and '''wish''' and any application embedding Tcl that calls ''Tcl_Main()'' provide it anyway. Also, new child interpreters don't get [argc] and [argv] set by default - set them if they need them. [argv0] describes the name of the top-level script that was invoked via tclsh or wish. [http://www.tcl.tk/man/tcl/UserCmd/tclsh.htm%|%tclsh man page]: [http://www.tcl.tk/man/tcl/UserCmd/wish.htm%|%wish man page]: Tk's Tk_ArgVInfo function makes a pass over the argv items, and handles some more arguments before placing the remainder in the argv list.. The arguments that these functions look for include: `-help`: print out a usage statment `-colormap`: specifies that the window should have a new private colormap `-display`: specify the display and screen to use `-file`: Ignored `-geometry`: specify the location and size of the window `-name`: used as title of the window and name of the interpreter `-sync`: synchronous X server commands `-use`: the main window of this app is to be embedded in another window `-visual`: specify which visual to use for the window. This means that you should not design your application to require flags of these names or even abbreviations of these! Otherwise, The argvinfo function in Tk grabs them before your application finds them. ---- See [command options] for a discussion of various options one has in parsing the argv (and argv-like) information. Also, note that [[[info script]] describes the name of the currently-executing script and this name even gets set by [source]. ''Technically, it is set by Tcl_FSEvalFile(), for those using Tcl's C API.'' The command [[[info nameofexecutable]]] describes the name of the executing binary, and might be thought more like the C level argv[[0]]. Some code available that helps process the argv arguments include: * [clig (Kirsch)] * [CmdLine] * [evaluate_parameters] Where: ftp://ftp.Lehigh.EDU/pub/evap/evap-2.x/evap-2.2.tar.Z ftp://ftp.procplace.com/pub/tcl/sorted/packages-7.6/devel/evap-2.1.tar.gz Description: evaluate_parameters is a Perl program that processes command line arguments in a simple consistent manner performing type-checking, multi-levels of help, etc. generate_tk_program is an auxiliary program which generates a Tcl/Tk GUI wrapper around one's Perl or C program to gather the command line arguments interactively. Updated: 10/1999 Contact: mailto:lusol@lehigh.edu (Stephen O. Lidie) * [getopt] * [ParseArgs] * [argp] * [argument parsing with defaults (Wagner)] * [argument processing for Tcl (Lehenbauer)] * [argument processing (Zimmer)] * [The Simple Development Library] [http://simpledevlib.sourceforge.net/] includes both a package for command arguments handling including typed arguments (with optional run-time checking) and options (SimpleProc, [http://simpledevlib.sourceforge.net/SimpleProc.html]) and a very powerful command line options parser with too many features to list here (SimpleOption, [http://simpledevlib.sourceforge.net/SimpleOption.html]). * sneaky_eval[http://tcltk.free.fr/index.php3?idxcat=100&page=21] Where: From the contact Description: Preprocess arguments before calling RecordAndEval or Eval, surrounding the arguments with braces so they won't be sub-evaluated. Updated: Contact: mailto:mdimeo@brooktree.com (Matt DiMeo) * SNTL[http://www.csua.berkeley.edu/%7Esls/woa/distrib/] Where: http://www.csua.berkeley.edu/%7Esls/woa/distrib/ ftp://ftp.procplace.com/pub/tcl/sorted/packages-7.6/devel/sntl-0.4.2.tar.gz ftp://ftp.procplace.com/pub/tcl/sorted/packages-7.6/devel/sntl-0.4.2p1.patch.tar.gz Description: A general Tcl library of procedures. Contains code to produce man pages from Tcl source, conversions from Tcl to C, HTML rendering, generating HTML, handling CGI forms, command line argument processing, a debugging message system, an object system, and various Tk widgets built with the object system. Updated: 10/1998 Contact: mailto:slshen@lbl.gov (Sam Shen) mailto:sls@aero.org (Sam Shen) * [variable argument process] * [yaap - Yet Another Argument Parsing utility] * [command options] ---- Schelte Bron wrote in [the comp.lang.tcl newsgroup] on 2004-02-19: ''I sometimes use numbers as variable names for a list of arguments like argv in the main script or args inside a proc.'' ====== set i 0; foreach n $argv {set [incr i] $n} ====== ''I can then refer to the arguments as $1, $2, etc. just like in sh/ksh/bash.'' [rdt] Uhh, can't you just have the proc use those name? i.e. ====== proc xyz {1 2 3} { # use the args as: puts "1=$1, 2=$2, 3=$3" } ====== What's wrong with that if that is what you want? [sbron]: There's nothing wrong with that, in a different situation. The point was having easy access to an unknown number of arguments. [rdt] I see. Yes that is additional capability, thanks. [MG]: adds that (especially when you're doing it outside a proc, and so the variables are all persistant) you should add an 'unset i n' to the end of the code above, just to clean up properly. <> Tcl syntax | Category Argument Processing | Category Internals | Arts and Crafts of Tcl-Tk Programming