[spambayes-dev] race conditions in imap filtering?

[Alon]

Agreed.  I only created the wrapper script after noticing two instances of 
imapfilter running late one night. It's a hack, but with proper cron timing 
it works.  But this is much better done within spambayes itself, with more 
fine-grain control, so users don't accidentally corrupt their data. 
Opening an exclusive lock on a file when running should do the trick nicely.

aLoN


> wrapper script that creates a /var/lock/spambayes.lck before execution
>
> Creating such a file in a naive fashion creates a race condition.  You
> might never get bitten by it, but any such code which goes into SpamBayes
> would have to use the proper mechanisms to create that file, otherwise
> someone will eventually run into it.  If you create it with the low-level
> os.open() function and the proper flags (some combination of O_EXCL,
> O_WRONLY and O_EXCLOCK) you should be good to go on Unix, Windows or Mac
> OS X.
>
> Skip
>