1 /*- 2 * Copyright (c) 2008 Ganbold Tsagaankhuu 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 */ 28 29 #include <sys/types.h> 30 #include <sys/wait.h> 31 #include <err.h> 32 #include <pthread.h> 33 #include <signal.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 #include <unistd.h> 38 39 #define NUM_THREADS 100 40 41 static void * 42 vfork_test(void *threadid __unused) 43 { 44 pid_t pid, wpid; 45 int status; 46 47 for (;;) { 48 pid = vfork(); 49 if (pid == 0) 50 _exit(0); 51 else if (pid == -1) 52 err(1, "Failed to vfork"); 53 else { 54 wpid = waitpid(pid, &status, 0); 55 if (wpid == -1) 56 err(1, "waitpid"); 57 } 58 } 59 return (NULL); 60 } 61 62 static void 63 sighandler(int signo __unused) 64 { 65 } 66 67 /* 68 * This program invokes multiple threads and each thread calls 69 * vfork() system call. 70 */ 71 int 72 main(void) 73 { 74 pthread_t threads[NUM_THREADS]; 75 struct sigaction reapchildren; 76 sigset_t sigchld_mask; 77 int rc, t; 78 79 memset(&reapchildren, 0, sizeof(reapchildren)); 80 reapchildren.sa_handler = sighandler; 81 if (sigaction(SIGCHLD, &reapchildren, NULL) == -1) 82 err(1, "Could not sigaction(SIGCHLD)"); 83 84 sigemptyset(&sigchld_mask); 85 sigaddset(&sigchld_mask, SIGCHLD); 86 if (sigprocmask(SIG_BLOCK, &sigchld_mask, NULL) == -1) 87 err(1, "sigprocmask"); 88 89 for (t = 0; t < NUM_THREADS; t++) { 90 rc = pthread_create(&threads[t], NULL, vfork_test, &t); 91 if (rc) 92 errc(1, rc, "pthread_create"); 93 } 94 pause(); 95 return (0); 96 } 97