gistfile1.pl

# * * *
# somewhere at startup
# * * *
$SIG{CHLD} = sub { while (waitpid(-1, WNOHANG) > 0) {} };

# * * *
# somewhere in the code
# * * *
use POSIX;

sub job {
    my ($job) = @_;

    unless (fork()) {
        my $exit = 0;
        unless (eval { $job->(); 1 })) {
            $exit = 1;
        }

        POSIX::_exit($exit);
    }
}

job(sub { say "hello world from child process (pid $$)" });