Exclusive flock will wait for previous exclusives to release before it will do its thing, i.e. it blocks. We flock on every file read & write, so yes, we are checking.

I've personally rewritten each of what used to be seperate file I/O routines to use what is now only a handful - all of which use the same model:

Verbatim from one of the routines:

    open(FILE, ">$path") or die "$! writing $path";
    &lock;    # calls flock(FLOCK_EX) and logs
    print FILE $string;
    &unlock;    # calls flock(FLOCK_UN) and logs
    close FILE;

[download]

(Yes, we are using strict... *FILE has been localized. The perils of inheriting someone else's work... :( :( :( )

Further thoughts? Thanks!

In reply to Re: Re: File locking, lock files, and how it all sucks by tocie
in thread File locking, lock files, and how it all sucks by tocie

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