diff --git a/src/userprog/process.c b/src/userprog/process.c
index e7f7e9035ca7a2376bcd79cc22b8a8a4bd68dbee..69a8daf1fdfad26946ad8bacd824c32a4dec4910 100644
--- a/src/userprog/process.c
+++ b/src/userprog/process.c
@@ -50,7 +50,8 @@ process_execute (const char *file_name)
     char *token;
     char *saveptr;
 
-    token = strtok_r(user_str, " ", &saveptr);
+
+    token = strtok_r(file_name, " ", &saveptr);
     if (token != NULL) { // split string using strtok_r function
         file_name_extracted = token;
 
@@ -71,7 +72,7 @@ process_execute (const char *file_name)
     
     int number_of_args=0; // to count how many args out of 3 passed to the stack 
 
-    printf("filename: %s\n", filename);
+    printf("filename: %s\n", file_name);
       if(args1!=NULL){
           printf("args1: %s\n", args1);
           number_of_args+=1;
diff --git a/src/userprog/syscall.c b/src/userprog/syscall.c
index 7980ce5a2aa53df479003f193b4f11119d1a68e0..19af13533cc35dfdbb2623346f75986cf1f96a12 100644
--- a/src/userprog/syscall.c
+++ b/src/userprog/syscall.c
@@ -38,7 +38,7 @@ syscall_handler (struct intr_frame *f UNUSED)
   switch(syscall_nr) {
 	  case SYS_HALT:{
 		  printf ("system call, halt\n");
-      shutdown_power_off();
+		      shutdown_power_off();
 		  break;
     }
     /*
@@ -91,3 +91,4 @@ syscall_handler (struct intr_frame *f UNUSED)
 }
   thread_exit ();
 }
+}