From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ross Johnson To: "Medina, Aurelio" Cc: Pthreads Developers List Subject: RE: read/write locks Date: Thu, 09 Sep 1999 22:21:00 -0000 Message-id: References: X-SW-Source: 1999/msg00086.html Hi, Re the read/write lock routines, I'll see if I can get them into the next snapshot, but it may be the one after so that I don't delay too long in getting recent bug fixes into the DLL. Ross On Thu, 9 Sep 1999, Medina, Aurelio wrote: > To all, > > Speaking of read/write locks, does anyone know if the POSIX read/write lock > routines (e.g. pthread_rwlock_init()) that I submitted will eventually > become part of the Pthreads-Win32 library? Seems like someone is already > working on another implementation. The routines that I submitted were > introduced in UNIX98 and are currently a X/Open standard. These routines > are portable and are currently available on HP-UX 11.0. > > Thanks, > Aurelio Medina > > -----Original Message----- > From: Mikael.Ambrus@elema.siemens.se > [SMTP:Mikael.Ambrus@elema.siemens.se] > Sent: Thursday, September 09, 1999 10:47 AM > To: pthreads-win32@sourceware.cygnus.com > 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 > > > +----------------------+---+ | Ross Johnson | | E-Mail: rpj@ise.canberra.edu.au | Info Sciences and Eng|___| | University of Canberra | FAX: +61 6 2015227 | PO Box 1 | | Belconnen ACT 2616 | WWW: http://willow.canberra.edu.au/~rpj/ | AUSTRALIA | +--------------------------+