http://qs321.pair.com?node_id=905367


in reply to Re^4: AnyEvent: How to protect critical sections?
in thread AnyEvent: How to protect critical sections?

This cannot work - if you expect ->lock() to block until the semaphore is released, how can it continue to execute the remaining code elsewhere?

I would either use a plain boolean variable, like you did in your first case, and keep the timer running:

my $critical; sub on_timer { if (! $critical) { ... }; };

... or manually restart the timer when it's allowed to restart again. The guard values returned from creating a timer allow you to conveniently stop a timer.