package Timed;

use strict;
use warnings;

use Exporter ();

our @ISA    = qw /Exporter/;
our @EXPORT = qw /timed_system/;


sub timed_system {
    my $time = shift;

    my $pid;
 
    local $SIG {ALRM} = sub {kill 15, $pid or die "kill: $!";
                             die "Timeout!"}; # Just SIGTERM.
 
    eval {
        $pid = fork;
 
        die "Fork failed: $!" unless defined $pid;
 
        unless ($pid) {
            exec @_;
            die "Exec failed: $!";
        }
 
        alarm $time;
 
        waitpid $pid => 0;
    };
    die $@ if $@ && $@ !~ /^Timeout!/;
}

1;
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Abigail

Thanks for the post, but do you know where I can get an example for the fork-exec solution, since in perlipc manual pages they mentioned that using eval-die can leave zombies and I would like to avoid that.

Thanks


Hotshot

Thanks for the post, but do you know where I can get an example for the fork-exec solution,

Did you actually bother to look at the code I posted?

They mentioned that using eval-die can leave zombies

As I said, the code I posted hasn't been finished yet. Work on it.

Abigail

You might want to consult man perlipc.

Abigail

If you happen to be on Microsoft Windows and are using the latest ActivePerl from http://www.activestate.com, you want to look at Win32::Job. Otherwise, listen to Abigail.

The caveat is that you need to be running Win2K or later. The job concept doesn't exist in earlier versions.

---

Examine what is said, not who speaks.

"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
Timing (and a little luck) are everything!

One that does not require the use of a fork:

#!c:/perl/bin/perl -w
$|++;

use strict;

sleep $ARGV[0] and exit if $ARGV[0];

eval {
  local $SIG{ALRM} = sub { die "timeout\n" };

  alarm 4; # change to timeout length
  system 'perl', $0, 6; # command to execute
  alarm 0;
};

warn "external command timed out: $@\n" if $@ eq "timeout\n";
print "continuing on, regardless of success/failure\n";
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The OP doesn't say one way or the other, but note that Abigail's kills the new process and Coruscate's does not.

For some example code, see Timing and timing out Unix commands and Timing Windows commands.

if you are trying to make alarm clock then you need a call back function for extra module. try to make a script that rotate the functions and check for its timeout. Again if you are trying to do something after reporting timeout.

my $time_out = 5;
my $flag = 1;
while(1){
    my $diff = time() - $starttime;
    if($diff >= $time_out){
        print "already reached maximum timeout\n";
        last;
    }
    if($flag){
        printData();
        $flag = 0;
    }
    sleep(1);
}
sub printData {
    print "i am running....\n";
}
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