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/cdefs.h> 30 #include <sys/types.h> 31 #include <sys/wait.h> 32 #include <err.h> 33 #include <pthread.h> 34 #include <signal.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <unistd.h> 39 40 #define NUM_THREADS 100 41 42 static void * 43 vfork_test(void *threadid __unused) 44 { 45 pid_t pid, wpid; 46 int status; 47 48 for (;;) { 49 pid = vfork(); 50 if (pid == 0) 51 _exit(0); 52 else if (pid == -1) 53 err(1, "Failed to vfork"); 54 else { 55 wpid = waitpid(pid, &status, 0); 56 if (wpid == -1) 57 err(1, "waitpid"); 58 } 59 } 60 return (NULL); 61 } 62 63 static void 64 sighandler(int signo __unused) 65 { 66 } 67 68 /* 69 * This program invokes multiple threads and each thread calls 70 * vfork() system call. 71 */ 72 int 73 main(void) 74 { 75 pthread_t threads[NUM_THREADS]; 76 struct sigaction reapchildren; 77 sigset_t sigchld_mask; 78 int rc, t; 79 80 memset(&reapchildren, 0, sizeof(reapchildren)); 81 reapchildren.sa_handler = sighandler; 82 if (sigaction(SIGCHLD, &reapchildren, NULL) == -1) 83 err(1, "Could not sigaction(SIGCHLD)"); 84 85 sigemptyset(&sigchld_mask); 86 sigaddset(&sigchld_mask, SIGCHLD); 87 if (sigprocmask(SIG_BLOCK, &sigchld_mask, NULL) == -1) 88 err(1, "sigprocmask"); 89 90 for (t = 0; t < NUM_THREADS; t++) { 91 rc = pthread_create(&threads[t], NULL, vfork_test, &t); 92 if (rc) 93 errc(1, rc, "pthread_create"); 94 } 95 pause(); 96 return (0); 97 } 98