Semaphores - feature request

It's impossible to correct remove semaphores with sem_remove function when I use them to provide execution of concurrent processes. When the last process releases the semaphore I should be able to remove it. But I don't know if another process haven't acquired the semaphore. For safety reasons I don't remove released semaphores from system. Now, If I get 128 semaphores and I execute sem_get one more time I will get warning. So, I can't remove semaphores (because I don't know if another process is using it) and I can't get next semaphore. I will try to tell about my sugestion. I assume that I have a function my_sem_remove($sem_id): function my_sem_remove($id) { if(Semaphore $id isn't acquired and its FIFO is empty) sem_remove($id); } None of instructions in this function can be interrupted. So, now the problem is simple to resolve: $id = sem_get(ID); sem_acquire($id); CRITICAL REGION sem_release($id); my_sem_remove($id); But now, two instructions: sem_release and my_sem_remove are not needed. It's simple to replace them by one function my_sem_release: function my_sem_release($id) { sem_release($id); my_sem_remove($id); } For reasons which about I will write later those instructions can't be interrupted. So, my example look like this: $id = sem_get(ID); sem_acquire($id); CRITICAL REGION my_sem_release($id); But let's imagine two concurrent processes executing code above: PROC1: $id = sem_get(ID); <--- interrupt PROC2: $id = sem_get(ID); sem_acquire($id); CRITICAL REGION my_sem_release($id); <--- interrupt PROC1: sem_acquire($id); <--- Uuups!! Error: semaphore doesn't exists, PROC2 has removed it. My solution: Instructions sem_get and sem_acquire can't be interrupted. So, I assume that there is a function my_sem_acquire: function my_sem_acquire($key, $max_acquire = 1, $perm = 0666, $auto_release = true) { $id = sem_get($key, $max_acquire, $perm, $auto_release); sem_acquire(); return $id; } None of instructions in function above can be interrupted. And finally correct example: $id = my_sem_acquire(SEMKEY); CRITICAL REGION my_sem_release($id); It's the best solution, without danger of operating on not existing semaphores. Also, unused semaphores are automaticcally removed. The problem is, that functions my_sem_acquire and my_sem_release can't be witten in PHP so it must be done in C inside source of PHP.Wojciech Malota