fork - How can I kill forked processes that take too long in my perl script without timing out the forked process? -

i've been using following template of forking/processes needs when comes processing "things" in parallel. loops through need process, x number of entries @ time, , time's out entries take long:

my $num_procs = 0; foreach $entry (@entries) {   $num_procs++;   if($num_procs == $max_procs) {     wait();     $num_procs--;   }   $pid = fork();   if($pid == 0) {     process($entry);   }  } (; $num_procs>0; $num_procs--) {   wait(); } 

the "process" routine has following template times out process:

my $timeout_in_seconds = 15; eval {   local $sig{alrm} = sub { die "alarm" };   alarm($timeout_in_seconds);           #    alarm(0); }; if ($@) {   # timeout }    

i've come across issue no longer works because child unable time out. (i think due i/o blocking issue nfs) way around this, i'm thinking, parent kill -9 child.

is there way modify code this?

whenever alarm can flaky, use case the poor man's alarm:

my $pid = fork(); if ($pid == 0) {     ...  # child code     exit; } if (fork() == 0) {     $time = 15;     exec($^x, "-e", "sleep 1,kill(0,$pid)||exit 1..$time;kill -9,$pid");     die; # shouldn't here  } 

the first fork fires off child process. second fork running process kill first process after $time seconds.