Add support for re-exec'ing with SIGHUP; equivalent to the already built-in

'restart' function.

calmwm.c

@@ -82,6 +82,8 @@ main(int argc, char **argv)
 
 	if (signal(SIGCHLD, sighdlr) == SIG_ERR)
 		err(1, "signal");
+	if (signal(SIGHUP, sighdlr) == SIG_ERR)
+		err(1, "signal");
 
 	Conf.homedir = getenv("HOME");
 	if ((Conf.homedir == NULL) || (Conf.homedir[0] == '\0')) {
@@ -221,6 +223,9 @@ sighdlr(int sig)
 		    (pid < 0 && errno == EINTR))
 			;
 		break;
+	case SIGHUP:
+		cwm_status = CWM_EXEC_WM;
+		break;
 	}
 
 	errno = save_errno;