pthread_attr_getinheritsched

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).

EXAMPLE
       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 5.05 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                             2017-09-15   PTHREAD_ATTR_SETINHERITSCHED(3)