exec() is not what you want. What you may want instead are either fork() or system() or do().

Some examples (without error checking, do a Super Search on each of these things to find out more):

  system( 'print.pl' );        
  # starts print.pl and continues when print.pl finishes

  # or alternatively

  do( 'print.pl' );            
  # Runs print.pl as if the text was typed instead of 
  # the do(...) line

  # or alternatively a version which is semi-portable to 
  # Windows as fork() dosen't really work there

  my $pid;
  $SIG{CHLD} = sub { wait };
  if ($pid = fork()) {
    # I am the master, so I continue here   
  } else {
    # I am the child, so I print
  };
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If you really really really want to use fork(), I recommend you use the Super Search and read the man pages about it, because there is much more to fork() than what I've touched on here.

Alternatively you might want to have a look at Proc::Daemon which might do just what you want

$foo = 'usr/bin/bar.pl';
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If anyone has any good reasons why not, please reply or /msg me.

Muchas gracias, Elgon

UPDATE: Thanks to myocom, that should read...

$foo = `/usr/bin/bar.pl`;
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Goddamn azerty keyboards!

Just two problems with your code: $foo = 'usr/bin/bar.pl';

One, those aren't backticks. Two, you probably want a leading / in your path, there...

$foo = `/usr/bin/bar.pl`;
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