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/* vi: set sw=4 ts=4: */
/*
* fork test for uClibc
*
* Copyright (C) 2000 by Lineo, inc. and Erik Andersen
* Copyright (C) 2000,2001 by Erik Andersen <andersen@uclibc.org>
* Written by Erik Andersen <andersen@uclibc.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Library General Public License as published by
* the Free Software Foundation; either version 2 of the License, 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 Library General Public License
* for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/wait.h>
#define GOT1 (1 << 1)
#define GOT2 (1 << 2)
#define GOT3 (1 << 3)
void child_handler(int sig)
{
fprintf(stderr, "I got a SIGCHLD\n");
}
int main(void)
{
pid_t pid1, pid2, pid3;
int status, result, wpid;
signal(SIGCHLD, child_handler);
if ((pid1 = fork()) == 0) {
fprintf(stderr, "The child process sleeps 2 seconds...\n");
sleep(4);
fprintf(stderr, "Child exiting.\n");
exit(-1);
}
if ((pid2 = fork()) == 0) {
fprintf(stderr, "The child process sleeps 3 seconds...\n");
sleep(3);
fprintf(stderr, "Child exiting.\n");
exit(-1);
}
if ((pid3 = fork()) == 0) {
fprintf(stderr, "The child process sleeps 4 seconds...\n");
sleep(2);
fprintf(stderr, "Child exiting.\n");
exit(-1);
}
fprintf(stderr, "Parent: waiting for the child to die.\n");
status = 0;
while (1) {
wpid = waitpid(pid1, &result, WNOHANG);
if (wpid == pid1)
status |= GOT1;
wpid = waitpid(pid2, &result, WNOHANG);
if (wpid == pid2)
status |= GOT2;
wpid = waitpid(pid3, &result, WNOHANG);
if (wpid == pid3)
status |= GOT3;
if (status == (GOT1 | GOT2 | GOT3))
break;
}
fprintf(stderr, "Child process exited.\nGoodbye.\n");
return EXIT_SUCCESS;
}
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/
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