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_getscope,  pthread_attr_setscope  — get and set the contentionscope attribute
       (REALTIME THREADS)

SYNOPSIS

       #include <pthread.h>

       int pthread_attr_getscope(const pthread_attr_t *restrict attr,
           int *restrict contentionscope);
       int pthread_attr_setscope(pthread_attr_t *attr, int contentionscope);

DESCRIPTION

       The pthread_attr_getscope() and pthread_attr_setscope() functions, respectively, shall get
       and set the contentionscope attribute in the attr object.

       The  contentionscope attribute may have the values PTHREAD_SCOPE_SYSTEM, signifying system
       scheduling contention  scope,  or  PTHREAD_SCOPE_PROCESS,  signifying  process  scheduling
       contention  scope.  The symbols PTHREAD_SCOPE_SYSTEM and PTHREAD_SCOPE_PROCESS are defined
       in the <pthread.h> header.

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

RETURN VALUE

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

ERRORS

       The pthread_attr_setscope() function shall fail if:

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

       The pthread_attr_setscope() function may fail if:

       EINVAL The value of contentionscope 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_getscope() or pthread_attr_setscope() 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_getinheritsched(), pthread_attr_getschedpolicy(),
       pthread_attr_getschedparam(), pthread_create()

       The Base Definitions volume of POSIX.1‐2008, <pthread.h>, <sched.h>

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1,  2013  Edition,  Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013  by  the
       Institute  of  Electrical  and  Electronics  Engineers,  Inc and The Open Group.  (This is
       POSIX.1-2008 with the  2013  Technical  Corrigendum  1  applied.)  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.unix.org/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 .