I have had really bad luck with signals. They can be âlostâ in more than one way. I thought this was the far more reliable and correct wayâ at least from that point of view. Jeremy From: Nathan Nobbe [mailto:quickshiftin@xxxxxxxxx] Sent: Monday, May 02, 2011 5:01 PM To: Jeremy Greene Cc: php-general@xxxxxxxxxxxxx Subject: Re: [PHP] semaphore release before acquire warning On Mon, May 2, 2011 at 2:57 PM, Jeremy Greene <jeremy@xxxxxxxxxx> wrote: Hi, I am getting a warning when calling sem_release() before (the same php script) calls sem_acquire(). I am doing this because it's a "signal" to another process. The other process (which happens to be C program) has done, or will do, a semop() to acquire the semaphore/signal. The actual data transfer is through shared memory. It does all functionally work quite nicely, but given that I'm getting the warning and that there doesn't seem to be any discussion of this at least in this list's archive maybe I'm putting a square peg into a round hole... or at least there's a rounder peg available. I did look into disabling the warning, but that got me more concerned since it seemed like a frowned upon thing to do and even more of a performance hit. The irony is that I'm using shared memory (and signals) exactly for performance reasons L perhaps try pcntl_signal() to signal the c program rather than sem_release(). -nathan