19 November 1997

    I have installed the following on Atlas and Artemis:
	Tcl 8.0
	Tk 8.0
	TclX 8.0.1
	Expect 5.25
The sources all live under /usr/local/src/tcl; the files needed
to run them are in various subdirectories of /usr/local/stow and
are linked into the appropriate places in /usr/local.
    Tcl stands for Tool Control Language and is a scripting
language that is easy to extend in various ways; the basic
program is an interpreter called "tclsh".  Tk is a graphical
extension of Tcl that includes a shell called "wish" for building
X Window programs (I guess it's like Visual Basic for Unix :-) ).
    TclX includes various extensions to Tcl and Tk; the extended
interpreter is called just "tcl" and the extended version of
"wish" is called "wishx".  
    Expect is a program for automating interactive programs.  As
a very simple example, you can set up a script to do the login
sequence for an anonymous ftp for you, so you don't have to type
"anonymous" and your email address every time.  I also have a
script to connect me to the text-based ACORN library catalogue
and skip all the introductory screens.  The basic program is
called "expect"; there is a version that adds Tk capabilities,
called "expectk".

    Note that Atlas already had DEC software subsets installed
that provide an older version (basically, version 7.4) of Tcl,
Tk, and TclX (but not Expect).  Unfortunately there is a system
package that depends on the Tcl subset, so it cannot be deleted. 
(Well, maybe it could since the new version is now present, but I
certainly don't want to try to figure out if that would break
anything.)  So, there are two versions of this stuff on Atlas. 
If you put /usr/local/bin at the beginning of your path you will
get the new version.  If anyone wants to use the function
libraries that come with Tcl/Tk/TclX, so that they need the "*.h"
and "lib*.so" files, they will have to be careful about
specifying the directories so that the correct version is used. 
There are major changes from version 7.4 to version 8.0, so this
could cause problems.

				Mark.