NAME
pthread_barrierattr_destroy
,
pthread_barrierattr_getpshared
,
pthread_barrierattr_init
,
pthread_barrierattr_setpshared
—
manipulate a barrier attribute
object
LIBRARY
library “libpthread”
SYNOPSIS
#include
<pthread.h>
int
pthread_barrierattr_destroy
(pthread_barrierattr_t
*attr);
int
pthread_barrierattr_getpshared
(const
pthread_barrierattr_t * restrict attr,
int * restrict
pshared);
int
pthread_barrierattr_init
(pthread_barrierattr_t
*attr);
int
pthread_barrierattr_setpshared
(pthread_barrierattr_t
*attr, int
pshared);
DESCRIPTION
Thepthread_barrierattr_init
()
function will initialize attr with default attributes.
The
pthread_barrierattr_destroy
()
function will destroy attr and release any resources
that may have been allocated on its behalf.
PTHREAD_PROCESS_PRIVATE
- The barrier object it is attached to may only be accessed by threads in the same process as the one that created the object.
PTHREAD_PROCESS_SHARED
- The barrier object it is attached to may be accessed by threads in processes other than the one that created the object.
RETURN VALUES
If successful, all these functions will return zero. Otherwise, an error number will be returned to indicate the error.
None of these functions will return
EINTR
.
ERRORS
The pthread_barrierattr_destroy
(),
pthread_barrierattr_getpshared
() and
pthread_barrierattr_setpshared
() functions may fail
if:
- [
EINVAL
] - The value specified by attr is invalid.
The pthread_barrierattr_init
() function
will fail if:
- [
ENOMEM
] - Insufficient memory to initialize the barrier attribute object attr.
The pthread_barrierattr_setpshared
()
function will fail if:
- [
EINVAL
] - The value specified in pshared is not one of the allowed values.
SEE ALSO
pthread_barrier_destroy(3), pthread_barrier_init(3), pthread_barrier_wait(3)
BUGS
The implementation of barriers does not fully conform to
IEEE Std 1003.2 (“POSIX.2”) because
the process-shared attribute is ignored; if any value other than
PTHREAD_PROCESS_PRIVATE
is specified in a call to
pthread_barrierattr_setpshared
(), it will return
EINVAL
.