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diff --git a/doc/tclsh.1 b/doc/tclsh.1 new file mode 100644 index 0000000..2922d81 --- /dev/null +++ b/doc/tclsh.1 @@ -0,0 +1,118 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +'\" SCCS: @(#) tclsh.1 1.13 96/08/26 13:00:15 +'\" +.so man.macros +.TH tclsh 1 "" Tcl "Tcl Applications" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +tclsh \- Simple shell containing Tcl interpreter +.SH SYNOPSIS +\fBtclsh\fR ?\fIfileName arg arg ...\fR? +.BE + +.SH DESCRIPTION +.PP +\fBTclsh\fR is a shell-like application that reads Tcl commands +from its standard input or from a file and evaluates them. +If invoked with no arguments then it runs interactively, reading +Tcl commands from standard input and printing command results and +error messages to standard output. +It runs until the \fBexit\fR command is invoked or until it +reaches end-of-file on its standard input. +If there exists a file \fB.tclshrc\fR in the home directory of +the user, \fBtclsh\fR evaluates the file as a Tcl script +just before reading the first command from standard input. + +.SH "SCRIPT FILES" +.PP +If \fBtclsh\fR is invoked with arguments then the first argument +is the name of a script file and any additional arguments +are made available to the script as variables (see below). +Instead of reading commands from standard input \fBtclsh\fR will +read Tcl commands from the named file; \fBtclsh\fR will exit +when it reaches the end of the file. +There is no automatic evaluation of \fB.tclshrc\fR in this +case, but the script file can always \fBsource\fR it if desired. +.PP +If you create a Tcl script in a file whose first line is +.CS +\fB#!/usr/local/bin/tclsh\fR +.CE +then you can invoke the script file directly from your shell if +you mark the file as executable. +This assumes that \fBtclsh\fR has been installed in the default +location in /usr/local/bin; if it's installed somewhere else +then you'll have to modify the above line to match. +Many UNIX systems do not allow the \fB#!\fR line to exceed about +30 characters in length, so be sure that the \fBtclsh\fR +executable can be accessed with a short file name. +.PP +An even better approach is to start your script files with the +following three lines: +.CS +\fB#!/bin/sh +# the next line restarts using tclsh \e +exec tclsh "$0" "$@"\fR +.CE +This approach has three advantages over the approach in the previous +paragraph. First, the location of the \fBtclsh\fR binary doesn't have +to be hard-wired into the script: it can be anywhere in your shell +search path. Second, it gets around the 30-character file name limit +in the previous approach. +Third, this approach will work even if \fBtclsh\fR is +itself a shell script (this is done on some systems in order to +handle multiple architectures or operating systems: the \fBtclsh\fR +script selects one of several binaries to run). The three lines +cause both \fBsh\fR and \fBtclsh\fR to process the script, but the +\fBexec\fR is only executed by \fBsh\fR. +\fBsh\fR processes the script first; it treats the second +line as a comment and executes the third line. +The \fBexec\fR statement cause the shell to stop processing and +instead to start up \fBtclsh\fR to reprocess the entire script. +When \fBtclsh\fR starts up, it treats all three lines as comments, +since the backslash at the end of the second line causes the third +line to be treated as part of the comment on the second line. + +.SH "VARIABLES" +.PP +\fBTclsh\fR sets the following Tcl variables: +.TP 15 +\fBargc\fR +Contains a count of the number of \fIarg\fR arguments (0 if none), +not including the name of the script file. +.TP 15 +\fBargv\fR +Contains a Tcl list whose elements are the \fIarg\fR arguments, +in order, or an empty string if there are no \fIarg\fR arguments. +.TP 15 +\fBargv0\fR +Contains \fIfileName\fR if it was specified. +Otherwise, contains the name by which \fBtclsh\fR was invoked. +.TP 15 +\fBtcl_interactive\fR +Contains 1 if \fBtclsh\fR is running interactively (no +\fIfileName\fR was specified and standard input is a terminal-like +device), 0 otherwise. + +.SH PROMPTS +.PP +When \fBtclsh\fR is invoked interactively it normally prompts for each +command with ``\fB% \fR''. You can change the prompt by setting the +variables \fBtcl_prompt1\fR and \fBtcl_prompt2\fR. If variable +\fBtcl_prompt1\fR exists then it must consist of a Tcl script +to output a prompt; instead of outputting a prompt \fBtclsh\fR +will evaluate the script in \fBtcl_prompt1\fR. +The variable \fBtcl_prompt2\fR is used in a similar way when +a newline is typed but the current command isn't yet complete; +if \fBtcl_prompt2\fR isn't set then no prompt is output for +incomplete commands. + +.SH KEYWORDS +argument, interpreter, prompt, script file, shell |