Well, regardless of what kind of program it was, GUI "toolkit" or commandline, you'd probably wanna use fork (some form of which any decent GUI will already do).

you wanna read perldoc perlfork, and do something like (this being the simple example, probably not useful)

use strict;

$| = 1; # disable buffering, read perldoc perlvar

my $pid = fork;

die "couldn't fork" unless defined $pid;

if($pid == 0) { # it's a kid
    print "type:";
    while(<STDIN>){
       print qq{you typed "$_"\n\ntype:"};
    }
} else {
   while(1) {
       print "\n\t\t",scalar localtime,"\n";
       sleep 1;
    }
}
[download]

GUI toolkits such as wxPerl and perlTk work much better for doing things like this, since well, they are gui tools. There is also various Curses modules on CPAN, for creating console gui programs (before windows, like dos), but I can't run any on windows ;)

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