sched_getcpu(3) — Linux manual page

sched_getcpu(3)          Library Functions Manual         sched_getcpu(3)

NAME         top

       sched_getcpu - determine CPU on which the calling thread is
       running

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <sched.h>

       int sched_getcpu(void);

   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):

       sched_getcpu():
           Since glibc 2.14:
               _GNU_SOURCE
           Before glibc 2.14:
               _BSD_SOURCE || _SVID_SOURCE
                   /* _GNU_SOURCE also suffices */

DESCRIPTION         top

       sched_getcpu() returns the number of the CPU on which the calling
       thread is currently executing.

RETURN VALUE         top

       On success, sched_getcpu() returns a nonnegative CPU number.  On
       error, -1 is returned and errno is set to indicate the error.

ERRORS         top

       ENOSYS This kernel does not implement getcpu(2).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ sched_getcpu()                       │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       GNU.

HISTORY         top

       glibc 2.6.

NOTES         top

       The call

           cpu = sched_getcpu();

       is equivalent to the following getcpu(2) call:

           int c, s;
           s = getcpu(&c, NULL);
           cpu = (s == -1) ? s : c;

SEE ALSO         top

       getcpu(2), sched(7)

COLOPHON         top

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Linux man-pages 6.15            2025-05-17                sched_getcpu(3)

Pages that refer to this page: getcpu(2),  sched_setaffinity(2),  pthread_setaffinity_np(3),  sched(7)

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