diff --git a/components/drivers/include/ipc/pipe.h b/components/drivers/include/ipc/pipe.h
index ddef3817df..94ac10f635 100644
--- a/components/drivers/include/ipc/pipe.h
+++ b/components/drivers/include/ipc/pipe.h
@@ -39,6 +39,11 @@ struct rt_pipe_device
 typedef struct rt_pipe_device rt_pipe_t;
 
 rt_pipe_t *rt_pipe_create(const char *name, int bufsz);
+rt_err_t rt_pipe_open(rt_device_t device, rt_uint16_t oflag);
+rt_ssize_t rt_pipe_read(rt_device_t device, rt_off_t pos, void *buffer, rt_size_t count);
+rt_ssize_t rt_pipe_write(rt_device_t device, rt_off_t pos, const void *buffer, rt_size_t count);
+rt_err_t rt_pipe_control(rt_device_t dev, int cmd, void *args);
+rt_err_t rt_pipe_close(rt_device_t device);
 int rt_pipe_delete(const char *name);
 
 #endif /* PIPE_H__ */
diff --git a/components/finsh/cmd.c b/components/finsh/cmd.c
index 8bb993a188..81e24bd1d2 100644
--- a/components/finsh/cmd.c
+++ b/components/finsh/cmd.c
@@ -51,14 +51,13 @@ static long clear(void)
 }
 MSH_CMD_EXPORT(clear, clear the terminal screen);
 
-extern void rt_show_version(void);
-long version(void)
+static long rtthread_version(void)
 {
     rt_show_version();
 
     return 0;
 }
-MSH_CMD_EXPORT(version, show RT-Thread version information);
+MSH_CMD_EXPORT(rtthread_version, show RT-Thread version information);
 
 rt_inline void object_split(int len)
 {
@@ -929,7 +928,7 @@ long list_device(void)
 #endif /* RT_USING_DEVICE */
 
 #ifndef FINSH_USING_OPTION_COMPLETION
-int cmd_list(int argc, char **argv)
+static int cmd_list(int argc, char **argv)
 {
     if(argc == 2)
     {
@@ -1042,7 +1041,7 @@ _usage:
 
 #else
 CMD_OPTIONS_STATEMENT(cmd_list)
-int cmd_list(int argc, char **argv)
+static int cmd_list(int argc, char **argv)
 {
     if (argc == 2)
     {
diff --git a/components/finsh/msh.c b/components/finsh/msh.c
index 319db5667b..4b1a39e8f8 100644
--- a/components/finsh/msh.c
+++ b/components/finsh/msh.c
@@ -32,7 +32,7 @@
 
 typedef int (*cmd_function_t)(int argc, char **argv);
 
-int msh_help(int argc, char **argv)
+static int msh_help(int argc, char **argv)
 {
     rt_kprintf("RT-Thread shell commands:\n");
     {
@@ -56,7 +56,7 @@ int msh_help(int argc, char **argv)
 MSH_CMD_EXPORT_ALIAS(msh_help, help, RT-Thread shell help);
 
 #ifdef MSH_USING_BUILT_IN_COMMANDS
-int cmd_ps(int argc, char **argv)
+static int cmd_ps(int argc, char **argv)
 {
     extern long list_thread(void);
     extern int list_module(void);
@@ -72,7 +72,7 @@ int cmd_ps(int argc, char **argv)
 MSH_CMD_EXPORT_ALIAS(cmd_ps, ps, List threads in the system);
 
 #ifdef RT_USING_HEAP
-int cmd_free(int argc, char **argv)
+static int cmd_free(int argc, char **argv)
 {
 #ifdef RT_USING_MEMHEAP_AS_HEAP
     extern void list_memheap(void);
diff --git a/components/finsh/shell.c b/components/finsh/shell.c
index db5f286285..0b17a75f00 100644
--- a/components/finsh/shell.c
+++ b/components/finsh/shell.c
@@ -448,7 +448,7 @@ static void shell_push_history(struct finsh_shell *shell)
 }
 #endif
 
-void finsh_thread_entry(void *parameter)
+static void finsh_thread_entry(void *parameter)
 {
     int ch;
 
@@ -690,7 +690,7 @@ void finsh_thread_entry(void *parameter)
     } /* end of device read */
 }
 
-void finsh_system_function_init(const void *begin, const void *end)
+static void finsh_system_function_init(const void *begin, const void *end)
 {
     _syscall_table_begin = (struct finsh_syscall *) begin;
     _syscall_table_end = (struct finsh_syscall *) end;
diff --git a/components/libc/compilers/armlibc/syscalls.c b/components/libc/compilers/armlibc/syscalls.c
index 5f7bcd0179..9998157178 100644
--- a/components/libc/compilers/armlibc/syscalls.c
+++ b/components/libc/compilers/armlibc/syscalls.c
@@ -25,6 +25,7 @@
 #ifdef RT_USING_POSIX_STDIO
 #include <posix/stdio.h>
 #endif /* RT_USING_POSIX_STDIO */
+#include <posix/stdlib.h>
 
 #define DBG_TAG    "armlibc.syscalls"
 #define DBG_LVL    DBG_INFO
@@ -312,7 +313,6 @@ void _ttywrch(int ch)
 /* for exit() and abort() */
 rt_weak void _sys_exit(int return_code)
 {
-    extern void __rt_libc_exit(int status);
     __rt_libc_exit(return_code);
     while (1);
 }
diff --git a/components/libc/compilers/common/cstdlib.c b/components/libc/compilers/common/cstdlib.c
index ee5dd58c50..d823322721 100644
--- a/components/libc/compilers/common/cstdlib.c
+++ b/components/libc/compilers/common/cstdlib.c
@@ -9,6 +9,7 @@
  */
 
 #include <rtthread.h>
+#include <posix/stdlib.h>
 
 #define DBG_TAG    "stdlib"
 #define DBG_LVL    DBG_INFO
diff --git a/components/libc/compilers/common/include/posix/stdlib.h b/components/libc/compilers/common/include/posix/stdlib.h
index bc53ebdecf..9f2e724369 100644
--- a/components/libc/compilers/common/include/posix/stdlib.h
+++ b/components/libc/compilers/common/include/posix/stdlib.h
@@ -18,6 +18,8 @@ extern "C" {
 #include <stdint.h>
 #include <stdlib.h>
 
+void __rt_libc_exit(int status);
+
 char *itoa(int n, char *buffer, int radix);
 char *lltoa(int64_t ll, char *buffer, int radix);
 char *ltoa(long l, char *buffer, int radix);
diff --git a/components/libc/compilers/dlib/syscalls.c b/components/libc/compilers/dlib/syscalls.c
index 391cbcac8a..328acc8bb1 100644
--- a/components/libc/compilers/dlib/syscalls.c
+++ b/components/libc/compilers/dlib/syscalls.c
@@ -9,11 +9,11 @@
  */
 
 #include <rtthread.h>
+#include <posix/stdlib.h>
 
 /* for exit() and abort() */
 void __exit (int status)
 {
-    extern void __rt_libc_exit(int status);
     __rt_libc_exit(status);
     while(1);
 }
diff --git a/components/libc/compilers/newlib/syscalls.c b/components/libc/compilers/newlib/syscalls.c
index ece5494b77..b311d7c712 100644
--- a/components/libc/compilers/newlib/syscalls.c
+++ b/components/libc/compilers/newlib/syscalls.c
@@ -23,6 +23,7 @@
 #ifdef RT_USING_POSIX_STDIO
 #include <posix/stdio.h>
 #endif /* RT_USING_POSIX_STDIO */
+#include <posix/stdlib.h>
 #ifdef RT_USING_MODULE
 #include <dlmodule.h>
 #endif /* RT_USING_MODULE */
@@ -326,7 +327,6 @@ _ssize_t _write_r(struct _reent *ptr, int fd, const void *buf, size_t nbytes)
 /* for exit() and abort() */
 __attribute__ ((noreturn)) void _exit (int status)
 {
-    extern void __rt_libc_exit(int status);
     __rt_libc_exit(status);
     while(1);
 }
diff --git a/components/libc/compilers/picolibc/exit.c b/components/libc/compilers/picolibc/exit.c
index f3f3ce831a..c4737a4a1b 100644
--- a/components/libc/compilers/picolibc/exit.c
+++ b/components/libc/compilers/picolibc/exit.c
@@ -9,11 +9,11 @@
 
 #include <rtthread.h>
 #include <sys/types.h>
+#include <posix/stdlib.h>
 
 /* for exit() and abort() */
 rt_noreturn void _exit (int status)
 {
-    extern void __rt_libc_exit(int status);
     __rt_libc_exit(status);
     while(1);
 }