Re: STL vector and multithreading

"Igor Tandetnik" <>
Fri, 16 Mar 2007 13:53:10 -0400
John <> wrote:

I have created a STL vector of callback functions that also allows the
programmer to specify a priority on which to be "called back". In my
main thread, routines exist to add callbacks (advise), remove
callbacks (unadvise) and change the priority level of an existing
callback, through the use of a cookie. After each access of the
vector I perform a sort on the specified priority level. All the
routines have been encapsulated by a mutex object.

Now in a worker thread I access this vector (using the same mutex)
iterate through the items and perform the callbacks on receipt of an
event from some hardware.

Now here is the problem, I am getting memory access errors and
occasionally mutex timeouts when I try to access the vector from
different locations in my program.

Show some code. You are doing something wrong. Specifically, you have
code that manipulates the vector outside of mutex protection.

Do you, by any chance, store iterators or pointers to elements of the
vector? You mention a cookie - what precisely is it? Also show the code
that iterates over the contents of the vector and performs the
callbacks - including mutex locks and unlocks.
With best wishes,
    Igor Tandetnik

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necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
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