Hendrik van Rooyen wrote: > Hi, > > I would like to do the following as one atomic operation: > > 1) Append an item to a list > 2) Set a Boolean indicator > > It would be almost like getting and holding the GIL, > to prevent a thread swap out between the two operations. > - sort of the inverted function than for which the GIL > seems to be used, which looks like "let go", get control > back via return from blocking I/O, and then "re - acquire" > > Is this "reversed" usage possible? > Is there some way to prevent thread swapping? > > The question arises in the context of a multi threaded > environment where the list is used as a single producer, > single consumer queue - I can solve my problem in various > ways, of which this is one, and I am curious as to if it is > possible to prevent a thread swap from inside the thread.
There have been discussions to make the GIL available from python code. But it is considered a implementation detail - and this is the reason you can't do what you need the way you want to. Just use a regular lock - in the end, that is what the GIL is anyway. And besides that, you don't "get" anything by your way, as the thread-scheduling itself isn't controlled by python - instead the OS threading implementation is used. Diez -- http://mail.python.org/mailman/listinfo/python-list
