Пакет: tcl

tclsh(1)		       Tcl Applications			      tclsh(1)



______________________________________________________________________________

NAME
       tclsh - Simple shell containing Tcl interpreter

SYNOPSIS
       tclsh ?-encoding name? ?fileName arg arg ...?
______________________________________________________________________________

DESCRIPTION
       Tclsh  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 stan‐
       dard input and printing command results and error messages to  standard
       output.	 It runs until the exit command is invoked or until it reaches
       end-of-file on its standard input.  If there exists a file .tclshrc (or
       tclshrc.tcl  on	the  Windows  platforms)  in the home directory of the
       user, interactive tclsh evaluates the file as a Tcl script just	before
       reading the first command from standard input.

SCRIPT FILES
       If tclsh is invoked with arguments then the first few arguments specify
       the name of a script file, and, optionally, the encoding	 of  the  text
       data  stored  in	 that  script  file. Any additional arguments are made
       available to the script as variables (see below).  Instead  of  reading
       commands	 from  standard	 input	tclsh  will read Tcl commands from the
       named file;  tclsh will exit when it reaches the end of the file.   The
       end of the file may be marked either by the physical end of the medium,
       or by the character, “\032” (“\u001a”, control-Z).  If  this  character
       is  present in the file, the tclsh application will read text up to but
       not including the character.  An application that requires this charac‐
       ter in the file may safely encode it as “\032”, “\x1A”, or “\u001a”; or
       may generate it by use of commands such as format or binary.  There  is
       no  automatic  evaluation of .tclshrc when the name of a script file is
       presented on the tclsh command line, but the  script  file  can	always
       source it if desired.

       If you create a Tcl script in a file whose first line is

	      #!/usr/local/bin/tclsh

       then  you  can  invoke  the script file directly from your shell if you
       mark the file as executable.  This assumes  that	 tclsh	has  been  in‐
       stalled	in the default location in /usr/local/bin;  if it is installed
       somewhere else then you will have to modify the above  line  to	match.
       Many  UNIX  systems do not allow the #! line to exceed about 30 charac‐
       ters in length, so be sure that the tclsh executable  can  be  accessed
       with a short file name.

       An  even better approach is to start your script files with the follow‐
       ing three lines:

	      #!/bin/sh
	      # the next line restarts using tclsh \
	      exec tclsh "$0" ${1+"$@"}

       This approach has three advantages over the approach  in	 the  previous
       paragraph.  First, the location of the tclsh binary does not 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 tclsh is it‐
       self  a	shell  script (this is done on some systems in order to handle
       multiple architectures or operating systems:  the tclsh script  selects
       one  of	several	 binaries  to run).  The three lines cause both sh and
       tclsh to process the script, but the exec is only executed by  sh.   sh
       processes the script first;  it treats the second line as a comment and
       executes the third line.	 The exec statement cause the  shell  to  stop
       processing  and	instead	 to  start  up	tclsh  to reprocess the entire
       script.	When tclsh 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.

       You should note that it is also common practice to install  tclsh  with
       its  version number as part of the name.	 This has the advantage of al‐
       lowing multiple versions of Tcl to exist on the same  system  at	 once,
       but  also  the  disadvantage  of making it harder to write scripts that
       start up uniformly across different versions of Tcl.

VARIABLES
       Tclsh sets the following global Tcl variables in addition to those cre‐
       ated  by	 the  Tcl  library itself (such as env, which maps environment
       variables such as PATH into Tcl):

       argc	      Contains a count of the number of arg  arguments	(0  if
		      none), not including the name of the script file.

       argv	      Contains	a  Tcl	list  whose elements are the arg argu‐
		      ments, in order, or an empty string if there are no  arg
		      arguments.

       argv0	      Contains	fileName if it was specified.  Otherwise, con‐
		      tains the name by which tclsh was invoked.

       tcl_interactive
		      Contains 1 if tclsh is running interactively  (no	 file‐
		      Name was specified and standard input is a terminal-like
		      device), 0 otherwise.

PROMPTS
       When tclsh is invoked interactively it normally prompts for  each  com‐
       mand  with “% ”.	 You can change the prompt by setting the global vari‐
       ables tcl_prompt1 and tcl_prompt2.  If variable tcl_prompt1 exists then
       it  must	 consist  of a Tcl script to output a prompt;  instead of out‐
       putting a prompt tclsh will evaluate the script	in  tcl_prompt1.   The
       variable	 tcl_prompt2  is used in a similar way when a newline is typed
       but the current command is not yet complete; if tcl_prompt2 is not  set
       then no prompt is output for incomplete commands.

STANDARD CHANNELS
       See Tcl_StandardChannels for more explanations.

SEE ALSO
       auto_path(n), encoding(n), env(n), fconfigure(n)

KEYWORDS
       application, argument, interpreter, prompt, script file, shell



Tcl								      tclsh(1)