man3p/pthread_barrierattr_getpshared.3p

   1 .\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
   2 .TH "PTHREAD_BARRIERATTR_GETPSHARED" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
   3 .\" pthread_barrierattr_getpshared
   4 .SH NAME
   5 pthread_barrierattr_getpshared, pthread_barrierattr_setpshared \- get
   6 and set the process\-shared attribute of the
   7 barrier attributes object (\fBADVANCED REALTIME THREADS\fP)
   8 .SH SYNOPSIS
   9 .LP
  10 \fB#include <pthread.h>
  11 .br
  12 .sp
  13 \fP
  14 .LP
  15 \fBint pthread_barrierattr_getpshared(const pthread_barrierattr_t
  16 *
  17 .br
  18 \ \ \ \ \ \  restrict\fP \fIattr\fP\fB, int *restrict\fP \fIpshared\fP\fB);
  19 .br
  20 int pthread_barrierattr_setpshared(pthread_barrierattr_t *\fP\fIattr\fP\fB,
  21 .br
  22 \ \ \ \ \ \  int\fP \fIpshared\fP\fB); \fP
  23 \fB
  24 .br
  25 \fP
  26 .SH DESCRIPTION
  27 .LP
  28 The \fIpthread_barrierattr_getpshared\fP() function shall obtain the
  29 value of the \fIprocess-shared\fP attribute from the
  30 attributes object referenced by \fIattr\fP. The \fIpthread_barrierattr_setpshared\fP()
  31 function shall set the
  32 \fIprocess-shared\fP attribute in an initialized attributes object
  33 referenced by \fIattr\fP.
  34 .LP
  35 The \fIprocess-shared\fP attribute is set to PTHREAD_PROCESS_SHARED
  36 to permit a barrier to be operated upon by any thread that
  37 has access to the memory where the barrier is allocated. If the \fIprocess-shared\fP
  38 attribute is PTHREAD_PROCESS_PRIVATE, the
  39 barrier shall only be operated upon by threads created within the
  40 same process as the thread that initialized the barrier; if
  41 threads of different processes attempt to operate on such a barrier,
  42 the behavior is undefined. The default value of the attribute
  43 shall be PTHREAD_PROCESS_PRIVATE. Both constants PTHREAD_PROCESS_SHARED
  44 and PTHREAD_PROCESS_PRIVATE are defined in \fI<pthread.h>\fP.
  45 .LP
  46 Additional attributes, their default values, and the names of the
  47 associated functions to get and set those attribute values are
  48 implementation-defined.
  49 .SH RETURN VALUE
  50 .LP
  51 If successful, the \fIpthread_barrierattr_getpshared\fP() function
  52 shall return zero and store the value of the
  53 \fIprocess-shared\fP attribute of \fIattr\fP into the object referenced
  54 by the \fIpshared\fP parameter. Otherwise, an error
  55 number shall be returned to indicate the error.
  56 .LP
  57 If successful, the \fIpthread_barrierattr_setpshared\fP() function
  58 shall return zero; otherwise, an error number shall be
  59 returned to indicate the error.
  60 .SH ERRORS
  61 .LP
  62 These functions may fail if:
  63 .TP 7
  64 .B EINVAL
  65 The value specified by \fIattr\fP is invalid.
  66 .sp
  67 .LP
  68 The \fIpthread_barrierattr_setpshared\fP() function may fail if:
  69 .TP 7
  70 .B EINVAL
  71 The new value specified for the \fIprocess-shared\fP attribute is
  72 not one of the legal values PTHREAD_PROCESS_SHARED or
  73 PTHREAD_PROCESS_PRIVATE.
  74 .sp
  75 .LP
  76 These functions shall not return an error code of [EINTR].
  77 .LP
  78 \fIThe following sections are informative.\fP
  79 .SH EXAMPLES
  80 .LP
  81 None.
  82 .SH APPLICATION USAGE
  83 .LP
  84 The \fIpthread_barrierattr_getpshared\fP() and \fIpthread_barrierattr_setpshared\fP()
  85 functions are part of the Barriers
  86 option and need not be provided on all implementations.
  87 .SH RATIONALE
  88 .LP
  89 None.
  90 .SH FUTURE DIRECTIONS
  91 .LP
  92 None.
  93 .SH SEE ALSO
  94 .LP
  95 \fIpthread_barrier_destroy\fP() , \fIpthread_barrierattr_destroy\fP()
  96 , \fIpthread_barrierattr_init\fP() , the Base Definitions volume of
  97 IEEE\ Std\ 1003.1-2001, \fI<pthread.h>\fP
  98 .SH COPYRIGHT
  99 Portions of this text are reprinted and reproduced in electronic form
 100 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
 101 -- Portable Operating System Interface (POSIX), The Open Group Base
 102 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
 103 Electrical and Electronics Engineers, Inc and The Open Group. In the
 104 event of any discrepancy between this version and the original IEEE and
 105 The Open Group Standard, the original IEEE and The Open Group Standard
 106 is the referee document. The original Standard can be obtained online at
 107 http://www.opengroup.org/unix/online.html .