diff --git a/lab5/user/lab5/apps/init.c b/lab5/user/lab5/apps/init.c
index 7531246..a607369 100644
--- a/lab5/user/lab5/apps/init.c
+++ b/lab5/user/lab5/apps/init.c
@@ -418,6 +418,14 @@ int fs_read(char *path, off_t offset, ssize_t count) {
     return ret;
 }
 
+void memcpy2(void *dst, const void *src, u64 len)
+{
+    u64 i = 0;
+    for (; i < len; i += 1) {
+        ((u8 *) dst)[i] = ((u8 *) src)[i];
+    }
+}
+
 /**
  * 读入文件并返回长度
  */
@@ -454,8 +462,16 @@ int fs_read_all(char *path, void **ret_buf)
             return cur;
         }
         // FIXME: 此处在 Release 模式下第一次读取前 16 字节为空
-        memcpy(buf, (const void *) TMPFS_READ_BUF_VADDR, cur);
-        memcpy(buf, (const void *) TMPFS_READ_BUF_VADDR, cur);
+        // memcpy(buf, (const void *) TMPFS_READ_BUF_VADDR, cur);
+        printf("first bytes: %c %c\n", ((u8*) TMPFS_READ_BUF_VADDR)[0],
+               ((u8*) TMPFS_READ_BUF_VADDR)[1]);
+        printf("memcpy %x %x %d\n", buf, (const void *) TMPFS_READ_BUF_VADDR, cur);
+        memcpy2(buf, (const void *) TMPFS_READ_BUF_VADDR, cur);
+//        u64 i = 0;
+//        for (; i < cur; i += 1) {
+//            ((u8 *) buf)[i] = ((u8 *) TMPFS_READ_BUF_VADDR)[i];
+//        }
+
         pos += cur;
         buf += cur;
     }
diff --git a/lab5/user/lab5/apps/init_test.c b/lab5/user/lab5/apps/init_test.c
index 58c6b66..4aa908e 100644
--- a/lab5/user/lab5/apps/init_test.c
+++ b/lab5/user/lab5/apps/init_test.c
@@ -43,6 +43,8 @@ int main()
 	usys_fs_load_cpio(CPIO_BIN);
 
 	boot_fs();
+    builtin_cmd("cat tar/cat_test.txt");
+    return 0;
 
 	test_readline();
 	test_echo();
diff --git a/lab5/user/lib/string.c b/lab5/user/lib/string.c
index 5f4893a..3f348a9 100644
--- a/lab5/user/lib/string.c
+++ b/lab5/user/lib/string.c
@@ -1,4 +1,5 @@
 #include <lib/type.h>
+#include "print.h"
 
 /*
  * A very shabby implementation, optimize it if you like.