add directory study

study/linux-travel/MINIX-1.5/1.5/Source/amoeba/util/master.c

@@ -0,0 +1,78 @@
+#include <signal.h>
+
+char console[] = "/dev/console";
+
+run(uid, gid, argv)
+char **argv;
+{
+
+	for (;;)
+		switch (fork()) {
+		default:
+			return;
+		case 0:
+			if (setgid(gid) < 0) perror("can't set gid");
+			if (setuid(uid) < 0) perror("can't set uid");
+/*
+			execvp(*argv, argv);
+*/
+			execv(*argv, argv);
+			perror("master: exec'ing");
+			prints("can't execute %s\n", *argv);
+/*
+			kill(getppid(), SIGTERM);
+*/
+			/* If the exec failed, don't try it again immediately.
+			 * Give the kernel a chance to do something else.
+			 */
+			sleep (5);
+			_exit(1);
+		case -1:
+			sleep(10);
+		}
+}
+
+main(argc, argv)
+char **argv;
+{
+  register n, uid, gid;
+
+  /* Minix can't do this
+	setpgrp(getpid(), getpid());
+  */
+	if (argc < 4) {
+		prints("Usage: master # uid gid command args ...\n");
+		return(1);
+	}
+	n = atoi(argv[1]);
+	if (n < 1 || n > 20) {
+		prints("Bad count.\n");
+		return(1);
+	}
+	signal(SIGHUP, SIG_IGN);
+	signal(SIGINT, SIG_IGN);
+	signal(SIGQUIT, SIG_IGN);
+
+/* Put the program into the background. */
+	switch (fork()) {
+	case 0:
+		break;
+	case -1:
+		perror(argv[0]);
+		return 1;
+	default:
+		return 0;
+	}
+	uid = atoi(argv[2]);
+	gid = atoi(argv[3]);
+
+/* Start n copies of the program. */
+	do
+		run(uid, gid, &argv[4]);
+	while (--n);
+
+/* Replace each one that dies. */
+	while (wait((int *) 0) > 0)
+		run(uid, gid, &argv[4]);
+	return(0);
+}