PTHREAD_BARRIERATTR_GETPSHARED(3C) Standard C Library Functions
NAME
pthread_barrierattr_getpshared, pthread_barrierattr_setpshared - get
and set process-shared attribute of barrier attributes object
SYNOPSIS
cc
-mt [
flag... ]
file... [
library... ]
#include <pthread.h>
int pthread_barrierattr_getpshared(
const pthread_barrierattr_t *restrict attr,
int *restrict pshared);
int pthread_barrierattr_setpshared(
pthread_barrierattr_t *attr,
int pshared);
DESCRIPTION
The
pthread_barrierattr_getpshared() function obtains the value of
the
process-shared attribute from the attributes object referenced by
attr. The
pthread_barrierattr_setpshared() function sets the
process- shared attribute in an initialized attributes object referenced by
attr.
The
process-shared attribute is set to
PTHREAD_PROCESS_SHARED to
permit a barrier to be operated upon by any thread that has access to
the memory where the barrier is allocated. If the
process-shared attribute is
PTHREAD_PROCESS_PRIVATE, the barrier will only be
operated upon by threads created within the same process as the
thread that initialized the barrier. If threads of different
processes attempt to operate on such a barrier, the behavior is
undefined.
The default value of the attribute is
PTHREAD_PROCESS_PRIVATE. Both
constants
PTHREAD_PROCESS_SHARED and
PTHREAD_PROCESS_PRIVATE are
defined in <
pthread.h>.
No barrier attributes other than the
process-shared attribute are
provided.
RETURN VALUES
Upon successful completion, the
pthread_barrierattr_getpshared() function returns 0 and stores the value of the
process-shared attribute of
attr into the object referenced by the
pshared parameter. Otherwise, an error number is returned to indicate the
error.
Upon successful completion, the
pthread_barrierattr_setpshared() function returns 0. Otherwise, an error number is returned to
indicate the error.
ERRORS
These functions may fail if:
EINVAL The value specified by
attr is invalid.
The
pthread_barrierattr_setpshared() function may fail if:
EINVAL The new value specified for the
process-shared attribute is
not one of the legal values
PTHREAD_PROCESS_SHARED or
PTHREAD_PROCESS_PRIVATE.
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+
SEE ALSO
pthread_barrier_init(3C),
pthread_barrierattr_destroy(3C),
attributes(7),
standards(7) January 30, 2004
PTHREAD_BARRIERATTR_GETPSHARED(3C)
