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_getinheritsched,  pthread_attr_setinheritsched — get and set the inheritsched
       attribute (REALTIME THREADS)

SYNOPSIS

       #include <pthread.h>

       int pthread_attr_getinheritsched(const pthread_attr_t *restrict attr,
           int *restrict inheritsched);
       int pthread_attr_setinheritsched(pthread_attr_t *attr,
           int inheritsched);

DESCRIPTION

       The   pthread_attr_getinheritsched()   and    pthread_attr_setinheritsched()    functions,
       respectively, shall get and set the inheritsched attribute in the attr argument.

       When  the  attributes  objects  are  used  by pthread_create(), the inheritsched attribute
       determines how the other scheduling attributes of the created thread shall be set.

       The supported values of inheritsched shall be:

       PTHREAD_INHERIT_SCHED
             Specifies that the thread scheduling attributes shall be inherited from the creating
             thread, and the scheduling attributes in this attr argument shall be ignored.

       PTHREAD_EXPLICIT_SCHED
             Specifies  that  the  thread scheduling attributes shall be set to the corresponding
             values from this attributes object.

       The  symbols  PTHREAD_INHERIT_SCHED  and  PTHREAD_EXPLICIT_SCHED  are   defined   in   the
       <pthread.h> header.

       The  following  thread  scheduling  attributes defined by POSIX.1‐2008 are affected by the
       inheritsched   attribute:   scheduling   policy   (schedpolicy),   scheduling   parameters
       (schedparam), and scheduling contention scope (contentionscope).

       The   behavior   is   undefined   if   the   value  specified  by  the  attr  argument  to
       pthread_attr_getinheritsched() or pthread_attr_setinheritsched()  does  not  refer  to  an
       initialized thread attributes object.

RETURN VALUE

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

ERRORS

       The pthread_attr_setinheritsched() function shall fail if:

       ENOTSUP
              An attempt was made to set the attribute to an unsupported value.

       The pthread_attr_setinheritsched() function may fail if:

       EINVAL The value of inheritsched is not valid.

       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.

       See  Section  2.9.4, Thread Scheduling for further details on thread scheduling attributes
       and their default settings.

RATIONALE

       If  an  implementation  detects  that  the  value  specified  by  the  attr  argument   to
       pthread_attr_getinheritsched()  or  pthread_attr_setinheritsched()  does  not  refer to an
       initialized thread attributes object, it is recommended that the function should fail  and
       report an [EINVAL] error.

FUTURE DIRECTIONS

       None.

SEE ALSO

       pthread_attr_destroy(), pthread_attr_getscope(), pthread_attr_getschedpolicy(),
       pthread_attr_getschedparam(), pthread_create()

       The Base Definitions volume of POSIX.1‐2017, <pthread.h>, <sched.h>

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1-2017,  Standard  for  Information Technology -- Portable Operating System Interface
       (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C)  2018  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 .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .