nptl/pthread_tryjoin.c

   1 /* Copyright (C) 2002-2021 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include "pthreadP.h"
  20
  21 int
  22 pthread_tryjoin_np (pthread_t threadid, void **thread_return)
  23 {
  24   /* Return right away if the thread hasn't terminated yet.  */
  25   struct pthread *pd = (struct pthread *) threadid;
  26   if (pd->tid != 0)
  27     return EBUSY;
  28
  29   /* If pd->tid == 0 then lll_wait_tid will not block on futex
  30      operation.  */
  31   return __pthread_clockjoin_ex (threadid, thread_return, 0 /* Ignored */,
  32                                  NULL, false);
  33 }