PTHREAD_ATTR_GETSCHEDPOLICY

Section: POSIX Programmer's Manual (3P)
Updated: 2003
Index Return to Main Contents
 

PROLOG

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

NAME

pthread_attr_getschedpolicy, pthread_attr_setschedpolicy - get and set the schedpolicy attribute (REALTIME THREADS)  

SYNOPSIS

#include <pthread.h>

int pthread_attr_getschedpolicy(const pthread_attr_t *restrict attr,
       int *restrict policy);
int pthread_attr_setschedpolicy(pthread_attr_t *attr, int policy);
 

DESCRIPTION

The pthread_attr_getschedpolicy() and pthread_attr_setschedpolicy() functions, respectively, shall get and set the schedpolicy attribute in the attr argument.

The supported values of policy shall include SCHED_FIFO, SCHED_RR, and SCHED_OTHER, which are defined in the <sched.h> header. When threads executing with the scheduling policy SCHED_FIFO, SCHED_RR, or SCHED_SPORADIC are waiting on a mutex, they shall acquire the mutex in priority order when the mutex is unlocked.  

RETURN VALUE

If successful, the pthread_attr_getschedpolicy() and pthread_attr_setschedpolicy() functions shall return zero; otherwise, an error number shall be returned to indicate the error.  

ERRORS

The pthread_attr_setschedpolicy() function may fail if:

EINVAL
The value of policy is not valid.
ENOTSUP
An attempt was made to set the attribute to an unsupported value.

These functions shall not return an error code of [EINTR].

The following sections are informative.  

EXAMPLES

None.  

APPLICATION USAGE

After these attributes have been set, a thread can be created with the specified attributes using pthread_create(). Using these routines does not affect the current running thread.  

RATIONALE

None.  

FUTURE DIRECTIONS

None.  

SEE ALSO

pthread_attr_destroy(), pthread_attr_getscope(), pthread_attr_getinheritsched(), pthread_attr_getschedparam(), pthread_create(), the Base Definitions volume of IEEE Std 1003.1-2001, <pthread.h>, <sched.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 .