mutex multi process sharing question

[mazzawi]

I know they can be shared if we use
pthread_mutexattr_setpshared with PTHREAD_PROCESS_SHARED

but does that only work if the processes are created with a fork,
after the mutex has been declared, ie

pthread_mutex_t DBMutex; /* mutex id */
fork();

so the processes know where to find the mutex.

but what if we have 2 indepednant processes. that are started
separately not forked. is there a way to use the pthread_mutex, or do
i have to use semaphores.

 

[mazzawi]

never mind guys it was covered here.

http://groups.google.ca/group/comp....read/thread/4b648d572415c512/d1ad10e09a0e92b0

summary forget it and use a semaphore.
if you really want to use a mutex you have to store it in a shm