Re: WaitForSingleObject() will not deadlock

Won't work. If you try to lock an object, and fail, then you can't legitimately tell if
you are the thread that originally locked it, or some other thread has it locked, so you
can't tell the validity of the has-been-visited flag, so it requires that you would pass
the entire locking sequence around so that if a try failed, you have to inspect the record
of all outstanding locks in the thread to see if there is an instance of the lock already
present. This means you have to deal with potentially unbounded sequences of locks in a
data structure, not a pleasant prospect.
joe

On Sun, 01 Jul 2007 23:43:56 -0700, Frank Cusack <fcusack@xxxxxxxxxxx> wrote:

On Mon, 02 Jul 2007 01:44:06 -0400 Joseph M. Newcomer <newcomer@xxxxxxxxxxxx> wrote:
But the issue is how can you lock and traverse a potentially
circular list with "node has been visited" detection without a
recursive mutex?

pthread_mutex_trylock()? or equivalent.
Joseph M. Newcomer [MVP]
email: newcomer@xxxxxxxxxxxx
Web: http://www.flounder.com
MVP Tips: http://www.flounder.com/mvp_tips.htm
.

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