Hello, I'm having some trouble understanding how fork() really works on ActiveState's Perl implementation. I would like to fork() a method multiple times that uses values derived from a data structure (like an array)..but I can't quite figure out how to wrap this (example below) code fragment into a foreach{} (or some such) that will track the completeness of the multiple pids.

I am using the example code found in question #714300. Here it is.. 


use POSIX":sys_wait_h";

my $pid = fork();
my $check;
die "can't fork:$?" unless(defined $pid);
if ($pid != 0) {
    print "I am the parent\n";
    my $flag = 0;
    while ($flag == 0) {
        $check = waitpid($pid,&WNOHANG);
        print "Waitpid returned $check\n";
        if ($check != 0) {
            print "Parent caught death of child $pid\n";
            $flag = 1;
        }
        else {
            sleep 1;    
            print "Not yet caught\n";
        }
    }
    print "Parent is exiting\n";
}    
else {
    print "I am the child\n";
    sleep 3;
    print "Child is exiting\n";
    exit (0);
}

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In reply to tracking multiple waitpid(s) by wxfield

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