pthread_condattr_setpshared.c 3.7 KB

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  1. /*
  2. * pthread_condattr_setpshared.c
  3. *
  4. * Description:
  5. * This translation unit implements condition variables and their primitives.
  6. *
  7. *
  8. * --------------------------------------------------------------------------
  9. *
  10. * Pthreads-win32 - POSIX Threads Library for Win32
  11. * Copyright(C) 1998 John E. Bossom
  12. * Copyright(C) 1999,2005 Pthreads-win32 contributors
  13. *
  14. * Contact Email: [email protected]
  15. *
  16. * The current list of contributors is contained
  17. * in the file CONTRIBUTORS included with the source
  18. * code distribution. The list can also be seen at the
  19. * following World Wide Web location:
  20. * http://sources.redhat.com/pthreads-win32/contributors.html
  21. *
  22. * This library is free software; you can redistribute it and/or
  23. * modify it under the terms of the GNU Lesser General Public
  24. * License as published by the Free Software Foundation; either
  25. * version 2 of the License, or (at your option) any later version.
  26. *
  27. * This library is distributed in the hope that it will be useful,
  28. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  29. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  30. * Lesser General Public License for more details.
  31. *
  32. * You should have received a copy of the GNU Lesser General Public
  33. * License along with this library in the file COPYING.LIB;
  34. * if not, write to the Free Software Foundation, Inc.,
  35. * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  36. */
  37. #include "pthread.h"
  38. #include "implement.h"
  39. int
  40. pthread_condattr_setpshared (pthread_condattr_t * attr, int pshared)
  41. /*
  42. * ------------------------------------------------------
  43. * DOCPUBLIC
  44. * Mutexes created with 'attr' can be shared between
  45. * processes if pthread_mutex_t variable is allocated
  46. * in memory shared by these processes.
  47. *
  48. * PARAMETERS
  49. * attr
  50. * pointer to an instance of pthread_mutexattr_t
  51. *
  52. * pshared
  53. * must be one of:
  54. *
  55. * PTHREAD_PROCESS_SHARED
  56. * May be shared if in shared memory
  57. *
  58. * PTHREAD_PROCESS_PRIVATE
  59. * Cannot be shared.
  60. *
  61. * DESCRIPTION
  62. * Mutexes creatd with 'attr' can be shared between
  63. * processes if pthread_mutex_t variable is allocated
  64. * in memory shared by these processes.
  65. *
  66. * NOTES:
  67. * 1) pshared mutexes MUST be allocated in shared
  68. * memory.
  69. *
  70. * 2) The following macro is defined if shared mutexes
  71. * are supported:
  72. * _POSIX_THREAD_PROCESS_SHARED
  73. *
  74. * RESULTS
  75. * 0 successfully set attribute,
  76. * EINVAL 'attr' or pshared is invalid,
  77. * ENOSYS PTHREAD_PROCESS_SHARED not supported,
  78. *
  79. * ------------------------------------------------------
  80. */
  81. {
  82. int result;
  83. if ((attr != NULL && *attr != NULL)
  84. && ((pshared == PTHREAD_PROCESS_SHARED)
  85. || (pshared == PTHREAD_PROCESS_PRIVATE)))
  86. {
  87. if (pshared == PTHREAD_PROCESS_SHARED)
  88. {
  89. #if !defined( _POSIX_THREAD_PROCESS_SHARED )
  90. result = ENOSYS;
  91. pshared = PTHREAD_PROCESS_PRIVATE;
  92. #else
  93. result = 0;
  94. #endif /* _POSIX_THREAD_PROCESS_SHARED */
  95. }
  96. else
  97. {
  98. result = 0;
  99. }
  100. (*attr)->pshared = pshared;
  101. }
  102. else
  103. {
  104. result = EINVAL;
  105. }
  106. return result;
  107. } /* pthread_condattr_setpshared */