1  /* Copyright (C) 1993-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <sys/types.h>
      19  #include <sys/wait.h>
      20  #include <errno.h>
      21  #include <hurd.h>
      22  #include <hurd/port.h>
      23  #include <not-cancel.h>
      24  
      25  pid_t
      26  __wait4_nocancel (pid_t pid, int *stat_loc, int options, struct rusage *usage)
      27  {
      28    pid_t dead;
      29    error_t err;
      30    struct rusage ignored;
      31    int sigcode;
      32    int dummy;
      33  
      34    err = __USEPORT (PROC, __proc_wait (port, pid, options,
      35  				      stat_loc ?: &dummy, &sigcode,
      36  				      usage ?: &ignored, &dead));
      37    switch (err)
      38      {
      39      case 0:			/* Got a child.  */
      40        return dead;
      41      case EAGAIN:
      42        /* The RPC returns this error when the WNOHANG flag is set and no
      43  	 selected children are dead (but some are living).  In that
      44  	 situation, our return value is zero.  (The RPC can't return zero
      45  	 for DEAD without also returning some garbage for the other out
      46  	 parameters, so an error return is much more natural here.  Hence
      47  	 the difference between the RPC and the POSIX.1 interface.  */
      48        return (pid_t) 0;
      49      default:
      50        return (pid_t) __hurd_fail (err);
      51      }
      52  }
      53  
      54  libc_hidden_def (__wait4_nocancel)