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(const 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 de-
termines 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 at-
tributes from the creating thread; the scheduling attributes in
attr are ignored.
PTHREAD_EXPLICIT_SCHED
Threads that are created using attr take their scheduling at-
tributes 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 attri-
bute 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 also documents an optional ENOTSUP error ("attempt was made to
set the attribute to an unsupported value") for pthread_attr_setinher-
itsched().
ATTRIBUTES
For an explanation of the terms used in this section, see at-
tributes(7).
+--------------------------------+---------------+---------+
|Interface | Attribute | Value |
+--------------------------------+---------------+---------+
|pthread_attr_setinheritsched(), | Thread safety | MT-Safe |
|pthread_attr_getinheritsched() | | |
+--------------------------------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
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 ob-
ject is set to SCHED_OTHER and the scheduling priority is set to 0.
However, if the inherit-scheduler attribute is then set to PTHREAD_EX-
PLICIT_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).
EXAMPLES
See pthread_setschedparam(3).
SEE ALSO
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), sched(7)
COLOPHON
This page is part of release 5.07 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
Linux 2020-06-09 PTHREAD_ATTR_SETINHERITSCHED(3)