- Improve error handling when daemonizing

ifstatd.c

@@ -197,6 +197,7 @@ daemon_start()
 	struct sigaction sig_action;
 	sigset_t sig_set;
 	pid_t otherpid;
+	int curPID;
 
 	tot = &ift;
 
@@ -218,10 +219,18 @@ daemon_start()
 			}
 			warn("Cannot open or create pidfile: %s", pid_filename);
 		}
-		/* fork ourselves if not asked otherwise */
-		if (fork()) {
+		/* start daemonizing */
+		curPID = fork();
+
+		switch (curPID) {
+		case 0:		/* This process is the child */
+			break;
+		case -1:		/* fork() failed, should exit */
+			return (EXIT_FAILURE);
+		default:		/* fork() successful, should exit */
 			return (EXIT_SUCCESS);
 		}
+
 		/* we are the child, complete the daemonization */
 
 		/* Close standard IO */
@@ -250,7 +259,8 @@ daemon_start()
 		sigaction(SIGINT, &sig_action, NULL);
 
 		/* create new session and process group */
-		setsid();
+		if (setsid() < 0)
+			return (EXIT_FAILURE);
 
 		/* persist pid */
 		pidfile_write(pfh);