55 lines
839 B
C
55 lines
839 B
C
/* fork.c COPYRIGHT FUJITSU LIMITED 2019 */
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#include <stdio.h>
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#include <unistd.h>
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#include <errno.h>
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <stdlib.h>
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static void waitChildren(void)
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{
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for (;;) {
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int status = 0;
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pid_t pid = wait(&status);
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if (pid == -1) {
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const char msg[] = "wait fail\n";
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if (errno == ECHILD) {
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return;
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} else if (errno == EINTR) {
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continue;
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}
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write(STDERR_FILENO, msg, sizeof(msg));
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_exit(-1);
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}
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}
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}
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int main(int argc, char **argv)
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{
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int ret = 0;
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int nr_fork;
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int i;
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if (argc < 2) {
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printf("usage: %s <nr_fork>\n", argv[0]);
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return 1;
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}
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nr_fork = atoi(argv[1]);
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for (i = 0; i < nr_fork; i++) {
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pid_t pid = fork();
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if (pid < 0) {
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perror("fork");
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ret = -1;
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break;
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} else if (pid == 0) {
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exit(0);
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}
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}
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waitChildren();
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return ret;
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}
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