diff --git a/components/dfs/filesystems/nfs/rpc/pmap.c b/components/dfs/filesystems/nfs/rpc/pmap.c
index fcf8e9d948f0e2ae15de9253f1c2e8dbbc94f4f2..4f2cf50c1e402704383ee03a7eaa00f19ab92565 100644
--- a/components/dfs/filesystems/nfs/rpc/pmap.c
+++ b/components/dfs/filesystems/nfs/rpc/pmap.c
@@ -24,7 +24,7 @@ unsigned short pmap_getport(struct sockaddr_in *address, unsigned long program,
 {
 	unsigned short port = 0;
 	int socket = -1;
-	register CLIENT *client;
+	register CLIENT *client = RT_NULL;
 	struct pmap parms;
 
 	address->sin_port = htons((unsigned short)PMAPPORT);
diff --git a/components/finsh/msh.c b/components/finsh/msh.c
index 1492e017e14f1670abe47f2a07460952c602ce43..49a5d235914f7020dfc9b1fd7e5ad4aabd66ea0e 100644
--- a/components/finsh/msh.c
+++ b/components/finsh/msh.c
@@ -180,7 +180,7 @@ static cmd_function_t msh_get_cmd(char *cmd, int size)
 #if defined(RT_USING_MODULE) && defined(RT_USING_DFS)
 /* Return 0 on module executed. Other value indicate error.
  */
-int msh_exec_module(char* cmd_line, int size)
+int msh_exec_module(const char* cmd_line, int size)
 {
     int ret;
     int fd = -1;
@@ -248,6 +248,11 @@ int msh_exec_module(char* cmd_line, int size)
     rt_free(pg_name);
     return ret;
 }
+
+int system(const char *command)
+{
+    return msh_exec_module(command, rt_strlen(command));
+}
 #endif
 
 static int _msh_exec_cmd(char* cmd, rt_size_t length, int *retp)
@@ -346,8 +351,8 @@ static int str_common(const char *str1, const char *str2)
 #ifdef RT_USING_DFS
 void msh_auto_complete_path(char *path)
 {
-    DIR* dir;
-    struct dirent *dirent;
+    DIR* dir = RT_NULL;
+    struct dirent *dirent = RT_NULL;
     char *full_path, *ptr, *index;
 
     full_path = (char*)rt_malloc(256);
diff --git a/components/finsh/shell.c b/components/finsh/shell.c
index 4313fcf6b2bf80664d1a61e713ca641eb39b852d..393d68713ccd72c99e7357602f6fcc846337dfa2 100644
--- a/components/finsh/shell.c
+++ b/components/finsh/shell.c
@@ -54,8 +54,10 @@ ALIGN(RT_ALIGN_SIZE)
 static char finsh_thread_stack[FINSH_THREAD_STACK_SIZE];
 struct finsh_shell* shell;
 
-#if defined(RT_USING_DFS) && defined(DFS_USING_WORKDIR)
+#if defined(FINSH_USING_MSH) || (defined(RT_USING_DFS) && defined(DFS_USING_WORKDIR))
+#if defined(RT_USING_DFS)
 #include <dfs_posix.h>
+#endif
 const char* finsh_get_prompt()
 {
     #define _MSH_PROMPT "msh "
@@ -68,8 +70,10 @@ const char* finsh_get_prompt()
 #endif
     strcpy(finsh_prompt, _PROMPT);
 
+#ifdef DFS_USING_WORKDIR
     /* get current working directory */
     getcwd(&finsh_prompt[rt_strlen(finsh_prompt)], RT_CONSOLEBUF_SIZE - rt_strlen(finsh_prompt));
+#endif
     strcat(finsh_prompt, ">");
 
     return finsh_prompt;
diff --git a/components/finsh/shell.h b/components/finsh/shell.h
index 9065f2f5ef7926588dc7f0bcb8d3a41276868d04..448f9e6fbe9ed7b172865068cc0146796112c7a6 100644
--- a/components/finsh/shell.h
+++ b/components/finsh/shell.h
@@ -43,7 +43,7 @@
 #define FINSH_CMD_SIZE		80
 
 #define FINSH_OPTION_ECHO	0x01
-#if defined(RT_USING_DFS) && defined(DFS_USING_WORKDIR)
+#if defined(FINSH_USING_MSH) || (defined(RT_USING_DFS) && defined(DFS_USING_WORKDIR))
 #define FINSH_PROMPT		finsh_get_prompt()
 const char* finsh_get_prompt(void);
 #else
diff --git a/include/rtthread.h b/include/rtthread.h
index abe3a614ed66c6858bde5a50126ddbcb00961f11..edd207bcb7751b35fe9fde0f24d539720d468705 100644
--- a/include/rtthread.h
+++ b/include/rtthread.h
@@ -421,7 +421,7 @@ rt_module_t rt_module_load(const char *name, void *module_ptr);
 rt_err_t rt_module_unload(rt_module_t module);
 #ifdef RT_USING_DFS
 rt_module_t rt_module_open(const char *filename);
-rt_module_t rt_module_exec_cmd(const char *path, char* cmd_line, int size);
+rt_module_t rt_module_exec_cmd(const char *path, const char* cmd_line, int size);
 #endif
 void *rt_module_malloc(rt_size_t size);
 void *rt_module_realloc(void *ptr, rt_size_t size);
diff --git a/src/module.c b/src/module.c
index 428d42e961f9c3934bd7abce8b633db128573e07..0603159b917caaf0f149fc1fc32b709195b74993 100644
--- a/src/module.c
+++ b/src/module.c
@@ -920,7 +920,7 @@ static void module_main_entry(void* parameter)
  *
  * @return the module object
  */
-rt_module_t rt_module_do_main(const char *name, void *module_ptr, char* cmd_line, int line_size)
+rt_module_t rt_module_do_main(const char *name, void *module_ptr, const char* cmd_line, int line_size)
 {
 	rt_module_t module;
 
@@ -1125,7 +1125,7 @@ rt_module_t rt_module_open(const char *path)
  *
  * @return the module object
  */
-rt_module_t rt_module_exec_cmd(const char *path, char* cmd_line, int size)
+rt_module_t rt_module_exec_cmd(const char *path, const char* cmd_line, int size)
 {
     struct stat s;
     int fd, length;