1PTHREAD_BARRIER_DESTROY(3P)POSIX Programmer's ManualPTHREAD_BARRIER_DESTROY(3P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 pthread_barrier_destroy, pthread_barrier_init — destroy and initialize
13 a barrier object
14
16 #include <pthread.h>
17 int pthread_barrier_destroy(pthread_barrier_t *barrier);
19 int pthread_barrier_init(pthread_barrier_t *restrict barrier,
20 const pthread_barrierattr_t *restrict attr, unsigned count);
21
23 The pthread_barrier_destroy() function shall destroy the barrier refer‐
24 enced by barrier and release any resources used by the barrier. The
25 effect of subsequent use of the barrier is undefined until the barrier
26 is reinitialized by another call to pthread_barrier_init(). An imple‐
27 mentation may use this function to set barrier to an invalid value. The
28 results are undefined if pthread_barrier_destroy() is called when any
29 thread is blocked on the barrier, or if this function is called with an
30 uninitialized barrier.
31 The pthread_barrier_init() function shall allocate any resources
33 required to use the barrier referenced by barrier and shall initialize
34 the barrier with attributes referenced by attr. If attr is NULL, the
35 default barrier attributes shall be used; the effect is the same as
36 passing the address of a default barrier attributes object. The results
37 are undefined if pthread_barrier_init() is called when any thread is
38 blocked on the barrier (that is, has not returned from the pthread_bar‐
39 rier_wait() call). The results are undefined if a barrier is used with‐
40 out first being initialized. The results are undefined if pthread_bar‐
41 rier_init() is called specifying an already initialized barrier.
42 The count argument specifies the number of threads that must call
44 pthread_barrier_wait() before any of them successfully return from the
45 call. The value specified by count must be greater than zero.
46 If the pthread_barrier_init() function fails, the barrier shall not be
48 initialized and the contents of barrier are undefined.
49 See Section 2.9.9, Synchronization Object Copies and Alternative Map‐
51 pings for further requirements.
52
54 Upon successful completion, these functions shall return zero; other‐
55 wise, an error number shall be returned to indicate the error.
56
58 The pthread_barrier_init() function shall fail if:
59 EAGAIN The system lacks the necessary resources to initialize another
61 barrier.
62 EINVAL The value specified by count is equal to zero.
64 ENOMEM Insufficient memory exists to initialize the barrier.
66 These functions shall not return an error code of [EINTR].
68 The following sections are informative.
70
72 None.
73
75 None.
76
78 If an implementation detects that the value specified by the barrier
79 argument to pthread_barrier_destroy() does not refer to an initialized
80 barrier object, it is recommended that the function should fail and
81 report an [EINVAL] error.
82 If an implementation detects that the value specified by the attr argu‐
84 ment to pthread_barrier_init() does not refer to an initialized barrier
85 attributes object, it is recommended that the function should fail and
86 report an [EINVAL] error.
87 If an implementation detects that the value specified by the barrier
89 argument to pthread_barrier_destroy() or pthread_barrier_init() refers
90 to a barrier that is in use (for example, in a pthread_barrier_wait()
91 call) by another thread, or detects that the value specified by the
92 barrier argument to pthread_barrier_init() refers to an already ini‐
93 tialized barrier object, it is recommended that the function should
94 fail and report an [EBUSY] error.
95
97 None.
98
100 pthread_barrier_wait()
101 The Base Definitions volume of POSIX.1‐2017, <pthread.h>
103
105 Portions of this text are reprinted and reproduced in electronic form
106 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
107 table Operating System Interface (POSIX), The Open Group Base Specifi‐
108 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
109 Electrical and Electronics Engineers, Inc and The Open Group. In the
110 event of any discrepancy between this version and the original IEEE and
111 The Open Group Standard, the original IEEE and The Open Group Standard
112 is the referee document. The original Standard can be obtained online
113 at http://www.opengroup.org/unix/online.html .
114 Any typographical or formatting errors that appear in this page are
116 most likely to have been introduced during the conversion of the source
117 files to man page format. To report such errors, see https://www.ker‐
118 nel.org/doc/man-pages/reporting_bugs.html .
119IEEE/The Open Group 2017 PTHREAD_BARRIER_DESTROY(3P)