I thought I read somewhere that Perl internally made sure any shared data accessed by threads would be in a consistent state, no matter if you lock the shared variable or not. In fact, I seem to recall it said it was quite safe to have one thread push stuff onto a shared array (ie, a queue), and another shift stuff off the other end of it, safely without any locking. Are you saying that on an SMP box the en-queue side might end up pushing garbage data onto the shared array, or that the de-queue side might read garbage data? Obviously it's okay if the reader side doesn't see anything yet, so long it just thinks that queue is undefined (empty) and just sleeps a while and checks again later on...

In reply to Re: point #4 by Anonymous Monk
in thread Thoughts on how to devise a queryable win32 service by noslenj123

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