1 /* 2 * pthread_mutexattr_getpshared.c 3 * 4 * Description: 5 * This translation unit implements mutual exclusion (mutex) primitives. 6 * 7 * -------------------------------------------------------------------------- 8 * 9 * Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems 10 * Copyright(C) 2008 Jason Schmidlapp 11 * 12 * Contact Email: jschmidlapp@users.sourceforge.net 13 * 14 * 15 * Based upon Pthreads-win32 - POSIX Threads Library for Win32 16 * Copyright(C) 1998 John E. Bossom 17 * Copyright(C) 1999,2005 Pthreads-win32 contributors 18 * 19 * Contact Email: rpj@callisto.canberra.edu.au 20 * 21 * The original list of contributors to the Pthreads-win32 project 22 * is contained in the file CONTRIBUTORS.ptw32 included with the 23 * source code distribution. The list can also be seen at the 24 * following World Wide Web location: 25 * http://sources.redhat.com/pthreads-win32/contributors.html 26 * 27 * This library is free software; you can redistribute it and/or 28 * modify it under the terms of the GNU Lesser General Public 29 * License as published by the Free Software Foundation; either 30 * version 2 of the License, or (at your option) any later version. 31 * 32 * This library is distributed in the hope that it will be useful, 33 * but WITHOUT ANY WARRANTY; without even the implied warranty of 34 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 35 * Lesser General Public License for more details. 36 * 37 * You should have received a copy of the GNU Lesser General Public 38 * License along with this library in the file COPYING.LIB; 39 * if not, write to the Free Software Foundation, Inc., 40 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA 41 */ 42 43 #include "pthread.h" 44 #include "implement.h" 45 46 47 int 48 pthread_mutexattr_getpshared (const pthread_mutexattr_t * attr, int *pshared) 49 /* 50 * ------------------------------------------------------ 51 * DOCPUBLIC 52 * Determine whether mutexes created with 'attr' can be 53 * shared between processes. 54 * 55 * PARAMETERS 56 * attr 57 * pointer to an instance of pthread_mutexattr_t 58 * 59 * pshared 60 * will be set to one of: 61 * 62 * PTHREAD_PROCESS_SHARED 63 * May be shared if in shared memory 64 * 65 * PTHREAD_PROCESS_PRIVATE 66 * Cannot be shared. 67 * 68 * 69 * DESCRIPTION 70 * Mutexes creatd with 'attr' can be shared between 71 * processes if pthread_mutex_t variable is allocated 72 * in memory shared by these processes. 73 * NOTES: 74 * 1) pshared mutexes MUST be allocated in shared 75 * memory. 76 * 2) The following macro is defined if shared mutexes 77 * are supported: 78 * _POSIX_THREAD_PROCESS_SHARED 79 * 80 * RESULTS 81 * 0 successfully retrieved attribute, 82 * EINVAL 'attr' is invalid, 83 * 84 * ------------------------------------------------------ 85 */ 86 { 87 int result; 88 89 if ((attr != NULL && *attr != NULL) && (pshared != NULL)) 90 { 91 *pshared = (*attr)->pshared; 92 result = 0; 93 } 94 else 95 { 96 result = EINVAL; 97 } 98 99 return (result); 100 101 } /* pthread_mutexattr_getpshared */ 102