NAME
pthread_mutexattr_getprioceiling, pthread_mutexattr_setprioceiling -
get and set the prioceiling attribute of the mutex attributes object
(REALTIME THREADS)
SYNOPSIS
#include <pthread.h>
int pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *
restrict attr, int *restrict prioceiling);
int pthread_mutexattr_setprioceiling(pthread_mutexattr_t *attr,
int prioceiling);
DESCRIPTION
The pthread_mutexattr_getprioceiling() and
pthread_mutexattr_setprioceiling() functions, respectively, shall get
and set the priority ceiling attribute of a mutex attributes object
pointed to by attr which was previously created by the function
pthread_mutexattr_init().
The prioceiling attribute contains the priority ceiling of initialized
mutexes. The values of prioceiling are within the maximum range of
priorities defined by SCHED_FIFO.
The prioceiling attribute defines the priority ceiling of initialized
mutexes, which is the minimum priority level at which the critical
section guarded by the mutex is executed. In order to avoid priority
inversion, the priority ceiling of the mutex shall be set to a priority
higher than or equal to the highest priority of all the threads that
may lock that mutex. The values of prioceiling are within the maximum
range of priorities defined under the SCHED_FIFO scheduling policy.
RETURN VALUE
Upon successful completion, the pthread_mutexattr_getprioceiling() and
pthread_mutexattr_setprioceiling() functions shall return zero;
otherwise, an error number shall be returned to indicate the error.
ERRORS
The pthread_mutexattr_getprioceiling() and
pthread_mutexattr_setprioceiling() functions may fail if:
EINVAL The value specified by attr or prioceiling is invalid.
EPERM The caller does not have the privilege to perform the operation.
These functions shall not return an error code of [EINTR].
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
pthread_cond_destroy() , pthread_create() , pthread_mutex_destroy() ,
the Base Definitions volume of IEEE Std 1003.1-2001, <pthread.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .