PTHREAD_MUTEXATTR_GETPRIOCEILING(3P)                POSIX Programmer's Manual               PTHREAD_MUTEXATTR_GETPRIOCEILING(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

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 func-
       tion 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,  Copy-
       right (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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                          PTHREAD_MUTEXATTR_GETPRIOCEILING(3P)