#!/usr/bin/perl

use strict;

use My_Functions;

&print_myheader();

my $br=(-t)?"\n":'<br />';

use POSIX qw(:signal_h);

my $sigset_new = POSIX::SigSet->new();
my $sigset_old = POSIX::SigSet->new();

sigprocmask(SIG_BLOCK, $sigset_new, $sigset_old);

if ($sigset_old->ismember(SIGALRM)) {
  print "SIGALRM is being blocked!$br";
  $sigset_new->addset(SIGALRM);
  sigprocmask(SIG_UNBLOCK, $sigset_new);
} else {
  print "SIGALRM NOT being blocked$br";
}

$SIG{ALRM} = sub {print scalar(localtime()), " ALARM, leaving$br"; sigprocmask(SIG_BLOCK, $sigset_new, $sigset_old); exit; };

alarm(5);

print scalar(localtime()), " Starting sleep...$br";

sleep (10);

print scalar(localtime()), " Exiting normally...$br";

##</code><code>##

[…. code …]

my $sigset_new = POSIX::SigSet->new();
my $sigset_old = POSIX::SigSet->new();

sigprocmask(SIG_BLOCK, $sigset_new, $sigset_old);

if ($sigset_old->ismember(SIGALRM))
{
$sigset_new->addset(SIGALRM);
sigprocmask(SIG_UNBLOCK, $sigset_new);
}
else
{
# do nothing
}

eval {

$SIG{ALRM}=sub{
   sigprocmask(SIG_BLOCK, $sigset_new, $sigset_old);
   exit;
};

alarm ($timer);

   for (@mylist)
   {
   my $cmd= "perl process_$_.pl args";  # tried with trailing & too
   system($cmd);
   }

alarm (0);
};

[ … more code …]