eval {
    local $SIG{ALRM} = sub { die "alarm timeout" };
    alarm $timeout;
    eval {
        # operation you're waiting on which might die()
    };
    alarm 0;        # cancel the alarm
    die $@ if $@;
};
alarm 0;            # race help
die $@ if $@ && $@ !~ /alarm timeout/;
if ($@) {
    # Whatever you want on an alarm timeout
}