man3/sched_getcpu.3

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  24 .TH SCHED_GETCPU 3 2009-12-08 "Linux" "Linux Programmer's Manual"
  25 .SH NAME
  26 sched_getcpu \- determine CPU on which the calling thread is running
  27 .SH SYNOPSIS
  28 .nf
  29 .B #define _GNU_SOURCE
  30 .B #include <sched.h>
  31
  32 .B int sched_getcpu(void);
  33 .fi
  34 .sp
  35 .in -4n
  36 Feature Test Macro Requirements for glibc (see
  37 .BR feature_test_macros (7)):
  38 .in
  39 .sp
  40 .BR sched_getcpu ():
  41 _BSD_SOURCE || _SVID_SOURCE
  42 .SH DESCRIPTION
  43 .BR sched_getcpu ()
  44 returns the number of the CPU on which the calling thread is currently executing.
  45 .SH RETURN VALUE
  46 On success,
  47 .BR sched_getcpu ()
  48 returns a nonnegative CPU number.
  49 On error, \-1 is returned and
  50 .I errno
  51 is set to indicate the error.
  52 .SH ERRORS
  53 .TP
  54 .B ENOSYS
  55 This kernel does not implement
  56 .BR getcpu (2).
  57 .SH VERSIONS
  58 This function is available since glibc 2.6.
  59 .SH CONFORMING TO
  60 .BR sched_getcpu ()
  61 is glibc specific.
  62 .SH NOTES
  63 The call
  64 .in +4n
  65 .nf
  66
  67 cpu = sched_getcpu();
  68
  69 .fi
  70 .in
  71 is equivalent to the following
  72 .BR getcpu (2)
  73 call:
  74 .in +4n
  75 .nf
  76
  77 int c, s;
  78 s = getcpu(&c, NULL, NULL);
  79 cpu = (s == -1) ? s : c;
  80 .fi
  81 .in
  82 .SH SEE ALSO
  83 .BR getcpu (2)