NAME
pthread_condattr_init
,
pthread_condattr_destroy
,
pthread_condattr_getclock
,
pthread_condattr_setclock
,
pthread_condattr_getpshared
,
pthread_condattr_setpshared
—
condition attribute
operations
LIBRARY
library “libpthread”
SYNOPSIS
#include
<pthread.h>
int
pthread_condattr_init
(pthread_condattr_t
*attr);
int
pthread_condattr_destroy
(pthread_condattr_t
*attr);
int
pthread_condattr_getclock
(const
pthread_condattr_t * restrict attr,
clockid_t * restrict
clock_id);
int
pthread_condattr_setclock
(pthread_condattr_t
*attr, clockid_t
clock_id);
int
pthread_condattr_getpshared
(const
pthread_condattr_t * restrict attr,
int * restrict
pshared);
int
pthread_condattr_setpshared
(pthread_condattr_t
*attr, int
pshared);
DESCRIPTION
Condition attribute objects are used to specify parameters topthread_cond_init
().
DragonFly's implementation of conditions does not
support any non-default attributes, so these functions are not very useful,
though they are required to be present by POSIX.
The
pthread_condattr_init
()
function initializes a condition attribute object with the default
attributes.
The
pthread_condattr_destroy
()
function destroys a condition attribute object.
The
pthread_condattr_getclock
()
function will put the value of the clock attribute from
attr into the memory area pointed to by
clock_id. The
pthread_condattr_setclock
()
function will set the clock attribute of attr to the
value specified in clock_id. The clock attribute
affects the interpretation of abstime in
pthread_cond_timedwait(3) and may be set to
CLOCK_REALTIME
(default) or
CLOCK_MONOTONIC
.
PTHREAD_PROCESS_PRIVATE
- The condition variable it is attached to may only be accessed by threads in the same process as the one that created the object.
RETURN VALUES
If successful, these functions return 0. Otherwise, an error number is returned to indicate the error.
ERRORS
The pthread_condattr_init
() function will
fail if:
- [
ENOMEM
] - Out of memory.
The pthread_condattr_destroy
() function
will fail if:
- [
EINVAL
] - Invalid value for attr.
The pthread_condattr_setclock
() function
will fail if:
- [
EINVAL
] - The value specified in clock_id is not one of the allowed values.
The pthread_condattr_setpshared
() function
will fail if:
- [
EINVAL
] - The value specified in pshared is not one of the allowed values.
SEE ALSO
STANDARDS
The pthread_condattr_init
() and
pthread_condattr_destroy
() functions conform to
ISO/IEC 9945-1:1996 (“POSIX.1”).