NAME
       tclsh - Simple shell containing Tcl interpreter

SYNOPSIS
       tclsh ?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 standard input and printing com-
       mand  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, 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 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 tclsh will
       read  Tcl  commands  from the named file;  tclsh will exit
       when it reaches the end of the file.  There  is  no  auto-
       matic  evaluation of .tclshrc in this case, 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 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 #! line to exceed about 30 char-
       acters 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 following three lines:
              #!/bin/sh
              # the next line restarts using tclsh \
              exec tclsh "$0" "$@"
       This approach has three advantages over  the  approach  in
       the  previous paragraph.  First, the location of the tclsh
       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 previ-
       ous  approach.   Third,  this  approach  will work even if
       tclsh is itself a shell  script  (this  is  done  on  some
       systems in order to handle multiple architectures or oper-
       ating 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 practise to install
       tclsh  with  its version number as part of the name.  This
       has the advantage of allowing multiple versions of Tcl  to
       exist  on  the same system at once, but also the disadvan-
       tage of making it harder to write scripts  that  start  up
       uniformly across different versions of Tcl.


VARIABLES
       Tclsh sets the following Tcl variables:

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

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

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

       tcl_interactive
                      Contains  1  if  tclsh  is running interac-
                      tively (no fileName was specified and stan-
                      dard  input  is  a terminal-like device), 0
                      otherwise.


PROMPTS
       When tclsh is invoked interactively  it  normally  prompts
       for  each  command with ``% ''.  You can change the prompt
       by setting the variables tcl_prompt1 and tcl_prompt2.   If
       variable  tcl_prompt1 exists then it must consist of a Tcl
       script to output a prompt;  instead of outputting a prompt
       tclsh  will evaluate the script in tcl_prompt1.  The vari-
       able tcl_prompt2 is used in a similar way when  a  newline
       is  typed  but  the current command isn't yet complete; if
       tcl_prompt2 isn't set then no prompt is output for  incom-
       plete commands.
KEYWORDS
       argument, interpreter, prompt, script file, shell
