Greetings ye Monks.

I have a loop that sleeps at the end and I want to make the thing bail out if the whole loop takes too long. The obvious solution:

alarm 10
while ( ! $done ) {
    $done = is_it_done_yet();
    sleep 1;
}

[download]

... is bad because perlfunc says:

It is usually a mistake to intermix "alarm" and "sleep" calls. ("sleep" may be internally implemented in your system with "alarm")

So what's the "right" way to do this?

Do I want to fork off a watcher process? Is there a simpler way? If there isn't a simpler way, is there a good CPAN module that handles this?

For background: I'm writing an apache log rotater. I want to compress the files once apache has stopped writing to them, which is what is_it_done_yet() is analogous to. My script checks to see if it can start compressing by using lsof (Unix::Lsof) and compresses them using gzip if it can. If lsof or gzip wander off and never return, I want to have some way to abort the whole thing.

Thanks!
--Pileofrogs

In reply to Alternatives to Mixing Alarm and Sleep by pileofrogs

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