It sounds more like you're looking for an alarm to go off after ten seconds, which will stop the subprocess. One way this can be done is by setting up an alarm handler to stop the current subprocess, and return control to the main routine for rerunning, error message, etc.

#!/usr/bin/perl

use strict;
use warnings;

local $| = 1;

# Our alarm handler: simply quits the
# process, or eval block.

  $SIG{ALRM} = sub { die "our alarm went off\n" };

# Put it all in an eval block, so we
# can regain control after if finishes
# or dies.

  eval {
    #alarm(10); # set for ten seconds  [example]
    alarm(1); # set for one second     [example]

    print "Running subprocess, etc...";
    sleep(5);  # the sleep() merely simulates a running process
    print "done\n";
  };

# Let's see if an error, from die, was
# returned; and if it was, whether it
# was because our alarm went off.

  if($@) {
    print "Timed out\n" if $@ =~ /our alarm went off/;
    # Do whatever else we wish.
  }
[download]

You can always wrap a while around the thing, so you can keep calling the subprocess.