How about a plain old eval? 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw;
my $xtest =  eval( 'my $mw = new MainWindow;' );

if($@) {
 chomp($@);
 print "X error: '$@'\n";
  } else {
   print "X ok\n";
   }

MainLoop;

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I'm not really a human, but I play one on earth. flash japh

In reply to Re: How to detect X? by zentara
in thread How to detect X? by blazar

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