Version 13 of tclsh

tclsh is an application created by default by the core distribution of tcl. It is a simple shell interpreter, and is frequently used by developers for writing and executing tcl scripts.

A user of tclsh (or of wish, the interactive tcl shell with Tk automatically loaded), should be aware that there are a few differences between typing tcl statements to the shell in interactive mode and saving tcl commands into a file and then asking tclsh to execute that command file.

The differences between tclsh in interactive mode and command file behavior include:

1. the tcl_interactive variable

interactive: this variable is set
command file: this variable is set to 0

2. unknown proc differences - if tclsh is unable to recognize a command, the unknown proc is invoked.

interactive: unknown will automatically pass the command string to exec .
command file: unknown will raise an error. The coder must code exec before any non-tcl commands.

3. command abbreviations

interactive: the unknown command looks to see if the typed command is an unambiguous abbreviation of an existing command and, if it is, invokes it. Thus in interactive mode it's possible to write

    set fp [op $myfile]

and see tclsh execute the open proc .

command file: coder is required to write the string open be written out in full.

4. standard output displayed

interactive: after tclsh executes a command, it writes the value of that command to the user's stdout screen.
command file: the coder must code a puts to get the output from a command to display to the stdout screen

5. byte-compilation

interactive: commands typed at a prompt are byte compiled
command file: top level commands (ones not coded within a proc) are not byte compiled

People writing scripts to be loaded from the tclsh command line should be aware that \u001a is an end-of-file character in scripts.

Category Application, a part of the Tcl package.