PTHREAD_ATTR_SETINHERITSCHED(3)     Linux Programmer's Manual     PTHREAD_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  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-scheduler  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 val‐
              ues specified by the attributes object.

       The default setting of the inherit-scheduler  attribute  in  a  newly  initialized  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().

ATTRIBUTES
   Multithreading (see pthreads(7))
       The   pthread_attr_setinheritsched()   and  pthread_attr_getinheritsched()  functions  are
       thread-safe.

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 schedul‐
       ing 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
       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 3.74 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 http://www.kernel.org/doc/man-pages/.



Linux                                       2014-05-21            PTHREAD_ATTR_SETINHERITSCHED(3)