diff --git a/README.md b/README.md
index b0809465..716d3581 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,12 @@ Tencent QQ group QQ群: 309957875<br />
 - add coap module
 
 # Change log
+2015-01-07<br />
+retrive more ram back.<br />
+add api file.format() to rebuild file system.<br />
+rename "NodeMcu" to "NodeMCU" in firmware.<br />
+add some check for file system op.
+
 2015-01-06<br />
 update sdk to 0.9.5.<br />
 pre_build bin now compiled by gcc toolchain.<br />
@@ -33,13 +39,6 @@ memory/heap usage optimized.<br />
 add support for multiple platform and toolchain include eclipse. <br />
 combine firmware for 512K, 1M, 2M, 4M flash to one. flash size auto-detected.
 
-2014-12-30<br />
-modify uart.on api, when run_input set to 0, uart.on now can read raw data from uart.<br />
-serial input now accept non-ascii chars.<br />
-fix dev-kit gpio map.<br />
-add setip, setmac, sleeptype api to wifi module. <br />
-add tmr.time() api to get rtc time and calibration.
-
 [more change log](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_en#change_log)<br />
 [更多变更日志](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_cn#change_log)
 
@@ -147,6 +146,7 @@ eagle.app.v6.irom0text.bin: 0x10000<br />
 esp_init_data_default.bin: 0x7c000<br />
 blank.bin: 0x7e000<br />
 
+*Better run file.format() after flash*
 
 #Connect the hardware in serial
 baudrate:9600
diff --git a/app/include/user_config.h b/app/include/user_config.h
index aae2c1b1..8e784520 100644
--- a/app/include/user_config.h
+++ b/app/include/user_config.h
@@ -6,7 +6,7 @@
 #define NODE_VERSION_REVISION	5U
 #define NODE_VERSION_INTERNAL   0U
 
-#define NODE_VERSION	"NodeMcu 0.9.5"
+#define NODE_VERSION	"NodeMCU 0.9.5"
 #define BUILD_DATE	    "build 20150107"
 
 // #define FLASH_512K
diff --git a/app/lua/lua.c b/app/lua/lua.c
index 43325550..ef9113f4 100644
--- a/app/lua/lua.c
+++ b/app/lua/lua.c
@@ -133,7 +133,7 @@ static int docall (lua_State *L, int narg, int clear) {
 
 static void print_version (void) {
   // l_message(NULL, LUA_RELEASE "  " LUA_COPYRIGHT);
-  l_message(NULL, NODE_VERSION " " BUILD_DATE "  powered by " LUA_RELEASE);
+  l_message(NULL, "\n" NODE_VERSION " " BUILD_DATE "  powered by " LUA_RELEASE);
 }
 
 
diff --git a/app/modules/file.c b/app/modules/file.c
index 22782de3..fa7628d3 100644
--- a/app/modules/file.c
+++ b/app/modules/file.c
@@ -11,7 +11,7 @@
 #include "flash_fs.h"
 #include "c_string.h"
 
-static int file_fd = FS_OPEN_OK - 1;
+static volatile int file_fd = FS_OPEN_OK - 1;
 
 // Lua: open(filename, mode)
 static int file_open( lua_State* L )
@@ -48,6 +48,22 @@ static int file_close( lua_State* L )
   return 0;  
 }
 
+// Lua: format()
+static int file_format( lua_State* L )
+{
+  size_t len;
+  file_close(L);
+  if( !fs_format() )
+  {
+    NODE_ERR( "\ni*** ERROR ***: unable to format. FS might be compromised.\n" );
+    NODE_ERR( "It is advised to re-flash the NodeMCU image.\n" );
+  }
+  else{
+    NODE_ERR( "format done.\n" );
+  }
+  return 0; 
+}
+
 #if defined(BUILD_WOFS)
 // Lua: list()
 static int file_list( lua_State* L )
@@ -63,22 +79,6 @@ static int file_list( lua_State* L )
   return 1;
 }
 
-// Lua: format()
-static int file_format( lua_State* L )
-{
-  size_t len;
-  file_close(L);
-  if( !fs_format() )
-  {
-    NODE_ERR( "\ni*** ERROR ***: unable to format. FS might be compromised.\n" );
-    NODE_ERR( "It is advised to re-flash the nodeMcu image.\n" );
-  }
-  else{
-    NODE_ERR( "format done.\n" );
-  }
-  return 0; 
-}
-
 #elif defined(BUILD_SPIFFS)
 
 extern spiffs fs;
@@ -275,8 +275,8 @@ const LUA_REG_TYPE file_map[] =
   { LSTRKEY( "writeline" ), LFUNCVAL( file_writeline ) },
   { LSTRKEY( "read" ), LFUNCVAL( file_read ) },
   { LSTRKEY( "readline" ), LFUNCVAL( file_readline ) },
-#if defined(BUILD_WOFS)
   { LSTRKEY( "format" ), LFUNCVAL( file_format ) },
+#if defined(BUILD_WOFS)
 #elif defined(BUILD_SPIFFS)
   { LSTRKEY( "remove" ), LFUNCVAL( file_remove ) },
   { LSTRKEY( "seek" ), LFUNCVAL( file_seek ) },
diff --git a/app/spiffs/spiffs.c b/app/spiffs/spiffs.c
index 005dab1a..84d57008 100644
--- a/app/spiffs/spiffs.c
+++ b/app/spiffs/spiffs.c
@@ -81,6 +81,7 @@ int myspiffs_format( void )
   while( sect_first <= sect_last )
     if( platform_flash_erase_sector( sect_first ++ ) == PLATFORM_ERR )
       return 0;
+  spiffs_mount();
   return 1;
 }
 
@@ -107,10 +108,20 @@ size_t myspiffs_write( int fd, const void* ptr, size_t len ){
     return len;
   }
 #endif
-  return SPIFFS_write(&fs, (spiffs_file)fd, (void *)ptr, len);
+  int res = SPIFFS_write(&fs, (spiffs_file)fd, (void *)ptr, len);
+  if (res < 0) {
+    NODE_DBG("write errno %i\n", SPIFFS_errno(&fs));
+    return 0;
+  }
+  return res;
 }
 size_t myspiffs_read( int fd, void* ptr, size_t len){
-  return SPIFFS_read(&fs, (spiffs_file)fd, ptr, len);
+  int res = SPIFFS_read(&fs, (spiffs_file)fd, ptr, len);
+  if (res < 0) {
+    NODE_DBG("read errno %i\n", SPIFFS_errno(&fs));
+    return 0;
+  }
+  return res;
 }
 int myspiffs_lseek( int fd, int off, int whence ){
   return SPIFFS_lseek(&fs, (spiffs_file)fd, off, whence);
@@ -123,8 +134,13 @@ int myspiffs_tell( int fd ){
 }
 int myspiffs_getc( int fd ){
   char c = EOF;
+  int res;
   if(!myspiffs_eof(fd)){
-    SPIFFS_read(&fs, (spiffs_file)fd, &c, 1);
+    res = SPIFFS_read(&fs, (spiffs_file)fd, &c, 1);
+    if (res != 1) {
+      NODE_DBG("getc errno %i\n", SPIFFS_errno(&fs));
+      return (int)EOF;
+    }
   }
   return (int)c;
 }
diff --git a/examples/fragment.lua b/examples/fragment.lua
index f4f8b11d..0699df4e 100644
--- a/examples/fragment.lua
+++ b/examples/fragment.lua
@@ -310,3 +310,5 @@ uart.on("data", 5 ,function(input) if input=="quit\r" then uart.on("data") else
 uart.on("data", 0 ,function(input) if input=="q" then uart.on("data") else print(input) end end, 0)
 
 uart.on("data","\r",function(input) if input=="quit" then uart.on("data") else print(input) end end, 1)
+
+for k, v in pairs(file.list()) do print('file:'..k..' len:'..v) end
diff --git a/pre_build/0.9.5/nodemcu_latest.bin b/pre_build/0.9.5/nodemcu_latest.bin
index 7b13f9cd..04f4dc31 100644
Binary files a/pre_build/0.9.5/nodemcu_latest.bin and b/pre_build/0.9.5/nodemcu_latest.bin differ
diff --git a/pre_build/latest/nodemcu_512k_latest.bin b/pre_build/latest/nodemcu_512k_latest.bin
index 7b13f9cd..04f4dc31 100644
Binary files a/pre_build/latest/nodemcu_512k_latest.bin and b/pre_build/latest/nodemcu_512k_latest.bin differ
diff --git a/pre_build/latest/nodemcu_latest.bin b/pre_build/latest/nodemcu_latest.bin
index 7b13f9cd..04f4dc31 100644
Binary files a/pre_build/latest/nodemcu_latest.bin and b/pre_build/latest/nodemcu_latest.bin differ