4 files changed, 8 insertions, 4 deletions
diff --git a/user/cat.c b/user/cat.c
index 598f005..520dc8b 100644
--- a/user/cat.c
+++ b/user/cat.c
@@ -1,5 +1,6 @@
 #include "kernel/types.h"
 #include "kernel/stat.h"
+#include "kernel/fcntl.h"
 #include "user/user.h"
 
 char buf[512];
@@ -32,7 +33,7 @@ main(int argc, char *argv[])
   }
 
   for(i = 1; i < argc; i++){
-    if((fd = open(argv[i], 0)) < 0){
+    if((fd = open(argv[i], O_RDONLY)) < 0){
       fprintf(2, "cat: cannot open %s\n", argv[i]);
       exit(1);
     }
diff --git a/user/grep.c b/user/grep.c
index 2315a0c..6c33766 100644
--- a/user/grep.c
+++ b/user/grep.c
@@ -2,6 +2,7 @@
 
 #include "kernel/types.h"
 #include "kernel/stat.h"
+#include "kernel/fcntl.h"
 #include "user/user.h"
 
 char buf[1024];
@@ -51,7 +52,7 @@ main(int argc, char *argv[])
   }
 
   for(i = 2; i < argc; i++){
-    if((fd = open(argv[i], 0)) < 0){
+    if((fd = open(argv[i], O_RDONLY)) < 0){
       printf("grep: cannot open %s\n", argv[i]);
       exit(1);
     }
diff --git a/user/ls.c b/user/ls.c
index c67b84b..b32c200 100644
--- a/user/ls.c
+++ b/user/ls.c
@@ -2,6 +2,7 @@
 #include "kernel/stat.h"
 #include "user/user.h"
 #include "kernel/fs.h"
+#include "kernel/fcntl.h"
 
 char*
 fmtname(char *path)
@@ -30,7 +31,7 @@ ls(char *path)
   struct dirent de;
   struct stat st;
 
-  if((fd = open(path, 0)) < 0){
+  if((fd = open(path, O_RDONLY)) < 0){
     fprintf(2, "ls: cannot open %s\n", path);
     return;
   }
diff --git a/user/wc.c b/user/wc.c
index 6a851ca..d8f3b2a 100644
--- a/user/wc.c
+++ b/user/wc.c
@@ -1,5 +1,6 @@
 #include "kernel/types.h"
 #include "kernel/stat.h"
+#include "kernel/fcntl.h"
 #include "user/user.h"
 
 char buf[512];
@@ -43,7 +44,7 @@ main(int argc, char *argv[])
   }
 
   for(i = 1; i < argc; i++){
-    if((fd = open(argv[i], 0)) < 0){
+    if((fd = open(argv[i], O_RDONLY)) < 0){
       printf("wc: cannot open %s\n", argv[i]);
       exit(1);
     }