man3/pthread_attr_setschedpolicy.3

   1 '\" t
   2 .\" Copyright (c) 2008 Linux Foundation, written by Michael Kerrisk
   3 .\"     <mtk.manpages@gmail.com>
   4 .\"
   5 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   6 .\"
   7 .TH pthread_attr_setschedpolicy 3 (date) "Linux man-pages (unreleased)"
   8 .SH NAME
   9 pthread_attr_setschedpolicy, pthread_attr_getschedpolicy \- set/get
  10 scheduling policy attribute in thread attributes object
  11 .SH LIBRARY
  12 POSIX threads library
  13 .RI ( libpthread ", " \-lpthread )
  14 .SH SYNOPSIS
  15 .nf
  16 .B #include <pthread.h>
  17 .P
  18 .BI "int pthread_attr_setschedpolicy(pthread_attr_t *" attr ", int " policy );
  19 .BI "int pthread_attr_getschedpolicy(const pthread_attr_t *restrict " attr ,
  20 .BI "                                int *restrict " policy );
  21 .fi
  22 .SH DESCRIPTION
  23 The
  24 .BR pthread_attr_setschedpolicy ()
  25 function sets the scheduling policy attribute of the
  26 thread attributes object referred to by
  27 .I attr
  28 to the value specified in
  29 .IR policy .
  30 This attribute determines the scheduling policy of
  31 a thread created using the thread attributes object
  32 .IR attr .
  33 .P
  34 The supported values for
  35 .I policy
  36 are
  37 .BR SCHED_FIFO ,
  38 .BR SCHED_RR ,
  39 and
  40 .BR SCHED_OTHER ,
  41 with the semantics described in
  42 .BR sched (7).
  43 .\" FIXME . pthread_setschedparam() places no restriction on the policy,
  44 .\" but pthread_attr_setschedpolicy() restricts policy to RR/FIFO/OTHER
  45 .\" http://sourceware.org/bugzilla/show_bug.cgi?id=7013
  46 .P
  47 The
  48 .BR pthread_attr_getschedpolicy ()
  49 returns the scheduling policy attribute of the thread attributes object
  50 .I attr
  51 in the buffer pointed to by
  52 .IR policy .
  53 .P
  54 In order for the policy setting made by
  55 .BR pthread_attr_setschedpolicy ()
  56 to have effect when calling
  57 .BR pthread_create (3),
  58 the caller must use
  59 .BR pthread_attr_setinheritsched (3)
  60 to set the inherit-scheduler attribute of the attributes object
  61 .I attr
  62 to
  63 .BR PTHREAD_EXPLICIT_SCHED .
  64 .SH RETURN VALUE
  65 On success, these functions return 0;
  66 on error, they return a nonzero error number.
  67 .SH ERRORS
  68 .BR pthread_attr_setschedpolicy ()
  69 can fail with the following error:
  70 .TP
  71 .B EINVAL
  72 Invalid value in
  73 .IR policy .
  74 .P
  75 POSIX.1 also documents an optional
  76 .B ENOTSUP
  77 error ("attempt was made to set the attribute to an unsupported value") for
  78 .BR pthread_attr_setschedpolicy ().
  79 .SH ATTRIBUTES
  80 For an explanation of the terms used in this section, see
  81 .BR attributes (7).
  82 .TS
  83 allbox;
  84 lbx lb lb
  85 l l l.
  86 Interface       Attribute       Value
  87 T{
  88 .na
  89 .nh
  90 .BR pthread_attr_setschedpolicy (),
  91 .BR pthread_attr_getschedpolicy ()
  92 T}      Thread safety   MT-Safe
  93 .TE
  94 .SH STANDARDS
  95 POSIX.1-2008.
  96 .SH HISTORY
  97 glibc 2.0.
  98 POSIX.1-2001.
  99 .SH EXAMPLES
 100 See
 101 .BR pthread_setschedparam (3).
 102 .SH SEE ALSO
 103 .ad l
 104 .nh
 105 .BR pthread_attr_init (3),
 106 .BR pthread_attr_setinheritsched (3),
 107 .BR pthread_attr_setschedparam (3),
 108 .BR pthread_create (3),
 109 .BR pthread_setschedparam (3),
 110 .BR pthread_setschedprio (3),
 111 .BR pthreads (7),
 112 .BR sched (7)