diff --git a/reboot/reboot.c b/reboot/reboot.c
index d9a4227..007dfba 100644
--- a/reboot/reboot.c
+++ b/reboot/reboot.c
@@ -35,7 +35,7 @@
 
         c = getopt(argc, argv, "p");
 
-        if (c == EOF) {
+        if (c == -1) {
             break;
         }