Changes the location of bison.simple after running bison on local
[findutils.git] / lib / waitpid.c
blobf2b423577e9132fcee70331457bbd727373ced52
1 /* Emulate waitpid on systems that just have wait.
2 Copyright 1994, 1995, 1998, 1999 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
7 any later version.
9 This program 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
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; see the file COPYING.
16 If not, write to the Free Software Foundation,
17 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19 #if HAVE_CONFIG_H
20 # include <config.h>
21 #endif
23 #include <errno.h>
24 #ifndef errno
25 extern int errno;
26 #endif
28 #define WAITPID_CHILDREN 8
29 static pid_t waited_pid[WAITPID_CHILDREN];
30 static int waited_status[WAITPID_CHILDREN];
32 pid_t
33 waitpid (pid_t pid, int *stat_loc, int options)
35 int i;
36 pid_t p;
38 if (!options && (pid == -1 || 0 < pid))
40 /* If we have already waited for this child, return it immediately. */
41 for (i = 0; i < WAITPID_CHILDREN; i++)
43 p = waited_pid[i];
44 if (p && (p == pid || pid == -1))
46 waited_pid[i] = 0;
47 goto success;
51 /* The child has not returned yet; wait for it, accumulating status. */
52 for (i = 0; i < WAITPID_CHILDREN; i++)
53 if (! waited_pid[i])
55 p = wait (&waited_status[i]);
56 if (p < 0)
57 return p;
58 if (p == pid || pid == -1)
59 goto success;
60 waited_pid[i] = p;
64 /* We cannot emulate this wait call, e.g. because of too many children. */
65 errno = EINVAL;
66 return -1;
68 success:
69 if (stat_loc)
70 *stat_loc = waited_status[i];
71 return p;