Personally I hate to see questions that are in fact FAQs or answered somewhere not too deep inside the docs, so I hope that this is not one such question. As a disclaimer I've checked perlfaq, PM, CPAN and Google: I have found some info, but not a short, definitive answer.

I would like to write a script that supports both a cmd line UI and a GUI (Tk), and in addition to cmd-line switches to activate one or the other, I'd like to it automatically start in GUI mode if an X server is available on the machine it's being launched.

In particular I gave a peek into the documentation of Tk itself, but it's really huge, and at a first glance I could not find anything relevant.

Also, once I find an answer to my question, I was thinking of organizing my program along these lines: 

#!/usr/bin/perl

use strict;
use warnings;
use File::Basename;
use FindBin qw/$Bin/;

my $name=basename $0;

# Code to detect X

exec $haveX ? "$Bin/$name.X" : "$Bin/$name.cmd";

__END__

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Of course in that case I would put most of the non-UI code into a module and call it from the respective '.X' and '.cmd' versions. Does this sound as a good idea or would you do it differently?

In reply to How to detect X? by blazar

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