PTHREAD_ATTR_SETINHERITSCHELinux Programmer's MPTHREAD_ATTR_SETINHERITSCHED(3)
NAME
pthread_attr_setinheritsched, pthread_attr_getinheritsched - set/get
inherit-scheduler attribute in thread attributes object
SYNOPSIS
#include <pthread.h>
int pthread_attr_setinheritsched(pthread_attr_t *attr,
int inheritsched);
int pthread_attr_getinheritsched(pthread_attr_t *attr,
int *inheritsched);
Compile and link with -pthread.
DESCRIPTION
The pthread_attr_setinheritsched() function sets the inherit-scheduler
attribute of the thread attributes object referred to by attr to the
value specified in inheritsched. The inherit-scheduler attribute
determines whether a thread created using the thread attributes object
attr will inherit its scheduling attributes from the calling thread or
whether it will take them from attr.
The following scheduling attributes are affected by the inherit-sched-
uler attribute: scheduling policy (pthread_attr_setschedpolicy(3)),
scheduling priority (pthread_attr_setschedparam(3)), and contention
scope (pthread_attr_setscope(3)).
The following values may be specified in inheritsched:
PTHREAD_INHERIT_SCHED
Threads that are created using attr inherit scheduling
attributes from the creating thread; the scheduling attributes
in attr are ignored.
PTHREAD_EXPLICIT_SCHED
Threads that are created using attr take their scheduling
attributes from the values specified by the attributes object.
The default setting of the inherit-scheduler attribute in a newly ini-
tialized thread attributes object is PTHREAD_INHERIT_SCHED.
The pthread_attr_getinheritsched() returns the inherit-scheduler
attribute of the thread attributes object attr in the buffer pointed to
by inheritsched.
RETURN VALUE
On success, these functions return 0; on error, they return a nonzero
error number.
ERRORS
pthread_attr_setinheritsched() can fail with the following error:
EINVAL Invalid value in inheritsched.
POSIX.1-2001 also documents an optional ENOTSUP error ("attempt was
made to set the attribute to an unsupported value") for
pthread_attr_setinheritsched().
CONFORMING TO
POSIX.1-2001.
BUGS
As at glibc 2.8, if a thread attributes object is initialized using
pthread_attr_init(3), then the scheduling policy of the attributes
object is set to SCHED_OTHER and the scheduling priority is set to 0.
However, if the inherit-scheduler attribute is then set to
PTHREAD_EXPLICIT_SCHED, then a thread created using the attribute
object wrongly inherits its scheduling attributes from the creating
thread. This bug does not occur if either the scheduling policy or
scheduling priority attribute is explicitly set in the thread
attributes object before calling pthread_create(3).
EXAMPLE
See pthread_setschedparam(3).
SEE ALSO
sched_setscheduler(2), pthread_attr_init(3),
pthread_attr_setschedparam(3), pthread_attr_setschedpolicy(3),
pthread_attr_setscope(3), pthread_create(3), pthread_setschedparam(3),
pthread_setschedprio(3), pthreads(7)
COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2013-04-19 PTHREAD_ATTR_SETINHERITSCHED(3)