You want an alarm, however with backticks this does leave the process hanging and there's no easy way to get its pid, but it is your child so you can do things to your process group to take it down, perhaps an END that sigkills the process group?

eval {
    local $SIG{ALRM} = sub { die "Alarma" };

    alarm 10;
    `perl -e 'while(1) {};'`;
    alarm 0;
};

if ($@ eq 'Alarma') {
    warn "alarm'd";
} elsif ($@) {
    die $@;
}

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In reply to Re: Timing out backquoted executions by Trizor
in thread Timing out backquoted executions by Anonymous Monk

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