/* * pthread_rwlockattr_setpshared.c * * Description: * This translation unit implements read/write lock primitives. * * -------------------------------------------------------------------------- * * Pthreads-win32 - POSIX Threads Library for Win32 * Copyright(C) 1998 John E. Bossom * Copyright(C) 1999,2005 Pthreads-win32 contributors * * Contact Email: rpj@callisto.canberra.edu.au * * The current list of contributors is contained * in the file CONTRIBUTORS included with the source * code distribution. The list can also be seen at the * following World Wide Web location: * http://sources.redhat.com/pthreads-win32/contributors.html * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library in the file COPYING.LIB; * if not, write to the Free Software Foundation, Inc., * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */ #include <limits.h> #include "pthread.h" #include "implement.h" int pthread_rwlockattr_setpshared (pthread_rwlockattr_t * attr, int pshared) /* * ------------------------------------------------------ * DOCPUBLIC * Rwlocks created with 'attr' can be shared between * processes if pthread_rwlock_t variable is allocated * in memory shared by these processes. * * PARAMETERS * attr * pointer to an instance of pthread_rwlockattr_t * * pshared * must be one of: * * PTHREAD_PROCESS_SHARED * May be shared if in shared memory * * PTHREAD_PROCESS_PRIVATE * Cannot be shared. * * DESCRIPTION * Rwlocks creatd with 'attr' can be shared between * processes if pthread_rwlock_t variable is allocated * in memory shared by these processes. * * NOTES: * 1) pshared rwlocks MUST be allocated in shared * memory. * * 2) The following macro is defined if shared rwlocks * are supported: * _POSIX_THREAD_PROCESS_SHARED * * RESULTS * 0 successfully set attribute, * EINVAL 'attr' or pshared is invalid, * ENOSYS PTHREAD_PROCESS_SHARED not supported, * * ------------------------------------------------------ */ { int result; if ((attr != NULL && *attr != NULL) && ((pshared == PTHREAD_PROCESS_SHARED) || (pshared == PTHREAD_PROCESS_PRIVATE))) { if (pshared == PTHREAD_PROCESS_SHARED) { #if !defined( _POSIX_THREAD_PROCESS_SHARED ) result = ENOSYS; pshared = PTHREAD_PROCESS_PRIVATE; #else result = 0; #endif /* _POSIX_THREAD_PROCESS_SHARED */ } else { result = 0; } (*attr)->pshared = pshared; } else { result = EINVAL; } return (result); } /* pthread_rwlockattr_setpshared */