/* Emulate waitpid on systems that just have wait. Copyright 1994, 1995, 1998, 1999 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #if HAVE_CONFIG_H # include <config.h> #endif #include <sys/types.h> #include <sys/stat.h> #include <errno.h> #ifndef errno extern int errno; #endif #define WAITPID_CHILDREN 8 static pid_t waited_pid[WAITPID_CHILDREN]; static int waited_status[WAITPID_CHILDREN]; pid_t waitpid (pid_t pid, int *stat_loc, int options) { int i; pid_t p; if (!options && (pid == -1 || 0 < pid)) { /* If we have already waited for this child, return it immediately. */ for (i = 0; i < WAITPID_CHILDREN; i++) { p = waited_pid[i]; if (p && (p == pid || pid == -1)) { waited_pid[i] = 0; goto success; } } /* The child has not returned yet; wait for it, accumulating status. */ for (i = 0; i < WAITPID_CHILDREN; i++) if (! waited_pid[i]) { p = wait (&waited_status[i]); if (p < 0) return p; if (p == pid || pid == -1) goto success; waited_pid[i] = p; } } /* We cannot emulate this wait call, e.g. because of too many children. */ errno = EINVAL; return -1; success: if (stat_loc) *stat_loc = waited_status[i]; return p; }