From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Scott Lightner" To: Subject: Re: pthread_cond_timedwait Date: Thu, 09 Sep 1999 09:21:00 -0000 Message-id: <00ab01befadf$934890d0$21122ecc@NEPTUNE2031> References: X-SW-Source: 1999/msg00082.html _ftime() will give you the current time with milliseconds. I believe struct timespec is in nanoseconds so you will lose some precision. Scott ----- Original Message ----- From: To: Sent: Thursday, September 09, 1999 11:47 AM Subject: pthread_cond_timedwait > [Ambrus Mikael] Dear pthreads colleagues, > > I'm writing a program that uses pthread_cond_timedwait. In the book > that I'm using (Pthreads Programming by Nicols, Buttlar & Proulux Farell ) > it says that this function should suspend the thread until some other thread > calls pthread_cond_signal, pthread_cond_broadcast OR the system timer is > greater than or equal to the third argument (abstime). > > Since clock_gettime is not implemented and I cant find some other > function that tells me the system time, I've tried to implement my own > version of clock_gettime by using the ansi function clock(). This function > returns the number of ticks that has elapsed since the program was started. > > But it seams that this is not the same absolute time that > pthread_cond_timedwait requires since the thread won't awaken. > > Is there another way to acquire the relevant system time? > > Another thing that has bothered me is that I recently downloaded the > latest snip of phtreads and now my read/write locks won't work. Since the > precompiled lib isn't recognised by the linker (neither with gcc v20.1 nor > MSVC 6.0) for some reason, I built the libs using the buildlib.bat provided. > Here's a snip of the code that fails: > > int pthread_rdwr_wunlock_np ( > pthread_rdwr_t *rdwrp > ){ > assert( pthread_mutex_lock(&(rdwrp->mutex)) == 0 ); > if (rdwrp->writers_writing == 0) { > assert( pthread_mutex_unlock(&(rdwrp->mutex)) == 0 ); > return(-1); > }else{ > rdwrp->writers_writing = 0; > assert(pthread_cond_broadcast(&(rdwrp->lock_free)) == 0); > > }; > > assert( pthread_mutex_unlock(&(rdwrp->mutex)) == 0 ); > return(0); > }; > > pthread_cond_broadcast returns EINVAL. Does anyone recognise this > problem? > > Wkr > Michael Ambrus > Siemens Elema > > >