1 files changed, 2 insertions, 2 deletions
diff --git a/user/kill.c b/user/kill.c
index 3e29cd0..f20c89f 100644
--- a/user/kill.c
+++ b/user/kill.c
@@ -9,9 +9,9 @@ main(int argc, char **argv)
 
   if(argc < 2){
     fprintf(2, "usage: kill pid...\n");
-    exit();
+    exit(-1);
   }
   for(i=1; i<argc; i++)
     kill(atoi(argv[i]));
-  exit();
+  exit(0);
 }