man3/pthread_yield.3

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  25 .TH PTHREAD_YIELD 3 2017-11-26 "Linux" "Linux Programmer's Manual"
  26 .SH NAME
  27 pthread_yield \- yield the processor
  28 .SH SYNOPSIS
  29 .nf
  30 .BR "#define _GNU_SOURCE" "             /* See feature_test_macros(7) */"
  31 .B #include <pthread.h>
  32 .PP
  33 .B int pthread_yield(void);
  34 .fi
  35 .PP
  36 Compile and link with \fI\-pthread\fP.
  37 .SH DESCRIPTION
  38 .BR pthread_yield ()
  39 causes the calling thread to relinquish the CPU.
  40 The thread is placed at the end of the run queue for its static
  41 priority and another thread is scheduled to run.
  42 For further details, see
  43 .BR sched_yield (2)
  44 .SH RETURN VALUE
  45 On success,
  46 .BR pthread_yield ()
  47 returns 0;
  48 on error, it returns an error number.
  49 .SH ERRORS
  50 On Linux, this call always succeeds
  51 (but portable and future-proof applications should nevertheless
  52 handle a possible error return).
  53 .SH ATTRIBUTES
  54 For an explanation of the terms used in this section, see
  55 .BR attributes (7).
  56 .TS
  57 allbox;
  58 lb lb lb
  59 l l l.
  60 Interface       Attribute       Value
  61 T{
  62 .BR pthread_yield ()
  63 T}      Thread safety   MT-Safe
  64 .TE
  65 .SH CONFORMING TO
  66 This call is nonstandard, but present on several other systems.
  67 Use the standardized
  68 .BR sched_yield (2)
  69 instead.
  70 .\" e.g., the BSDs, Tru64, AIX, and Irix.
  71 .SH NOTES
  72 On Linux, this function is implemented as a call to
  73 .BR sched_yield (2).
  74 .PP
  75 .BR pthread_yield ()
  76 is intended for use with real-time scheduling policies (i.e.,
  77 .BR SCHED_FIFO
  78 or
  79 .BR SCHED_RR ).
  80 Use of
  81 .BR pthread_yield ()
  82 with nondeterministic scheduling policies such as
  83 .BR SCHED_OTHER
  84 is unspecified and very likely means your application design is broken.
  85 .SH SEE ALSO
  86 .BR sched_yield (2),
  87 .\" FIXME . .BR pthread_cond_wait (3),
  88 .BR pthreads (7),
  89 .BR sched (7)