diff --git a/components/dfs/SConscript b/components/dfs/SConscript
index 3ccaeb10803b3e056a478644f6ea0d863b10d8aa..e449c849114ac9e88d1ba1d627f990901707da93 100644
--- a/components/dfs/SConscript
+++ b/components/dfs/SConscript
@@ -11,7 +11,7 @@ cwd = GetCurrentDir()
 CPPPATH = [cwd + "/include"]
 
 if GetDepend('RT_USING_POSIX'):
-    src += ['src/poll.c', 'src/select.c']
+    src += ['src/dfs_poll.c', 'src/dfs_select.c']
 
 group = DefineGroup('Filesystem', src, depend = ['RT_USING_DFS'], CPPPATH = CPPPATH)
 
diff --git a/components/dfs/include/dfs_poll.h b/components/dfs/include/dfs_poll.h
index 096a5fe712433ee776afa8a6b7026a0e41f66979..11d17cc1ff3619461847679e2e7bff9be68eeaa2 100644
--- a/components/dfs/include/dfs_poll.h
+++ b/components/dfs/include/dfs_poll.h
@@ -10,37 +10,6 @@
 #ifndef DFS_POLL_H__
 #define DFS_POLL_H__
 
-#include <rtthread.h>
-
-#ifdef RT_USING_POSIX
-#include <sys/time.h> /* for struct timeval */
-
-#if !defined(POLLIN) && !defined(POLLOUT)
-#define POLLIN          (0x01)
-#define POLLRDNORM      (0x01)
-#define POLLRDBAND      (0x01)
-#define POLLPRI         (0x01)
-
-#define POLLOUT         (0x02)
-#define POLLWRNORM      (0x02)
-#define POLLWRBAND      (0x02)
-
-#define POLLERR         (0x04)
-#define POLLHUP         (0x08)
-#define POLLNVAL        (0x10)
-
-typedef unsigned int nfds_t;
-
-struct pollfd
-{
-    int fd;
-    short events;
-    short revents;
-};
-#endif /* !defined(POLLIN) && !defined(POLLOUT) */
-
-#define POLLMASK_DEFAULT (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)
-int poll(struct pollfd *fds, nfds_t nfds, int timeout);
-#endif /* RT_USING_POSIX */
+#include <poll.h>
 
 #endif /* DFS_POLL_H__ */
diff --git a/components/dfs/src/poll.c b/components/dfs/src/dfs_poll.c
similarity index 100%
rename from components/dfs/src/poll.c
rename to components/dfs/src/dfs_poll.c
diff --git a/components/dfs/src/select.c b/components/dfs/src/dfs_select.c
similarity index 100%
rename from components/dfs/src/select.c
rename to components/dfs/src/dfs_select.c
diff --git a/components/libc/compilers/common/poll.h b/components/libc/compilers/common/poll.h
new file mode 100644
index 0000000000000000000000000000000000000000..1862373559bb03fe468c9b6f0b920c842bca082d
--- /dev/null
+++ b/components/libc/compilers/common/poll.h
@@ -0,0 +1,40 @@
+#ifndef __POLL_H__
+#define __POLL_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if !defined(POLLIN) && !defined(POLLOUT)
+#define POLLIN          (0x01)
+#define POLLRDNORM      (0x01)
+#define POLLRDBAND      (0x01)
+#define POLLPRI         (0x01)
+
+#define POLLOUT         (0x02)
+#define POLLWRNORM      (0x02)
+#define POLLWRBAND      (0x02)
+
+#define POLLERR         (0x04)
+#define POLLHUP         (0x08)
+#define POLLNVAL        (0x10)
+
+typedef unsigned int nfds_t;
+
+struct pollfd
+{
+    int fd;
+    short events;
+    short revents;
+};
+#endif /* !defined(POLLIN) && !defined(POLLOUT) */
+
+#define POLLMASK_DEFAULT (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)
+
+int poll(struct pollfd *fds, nfds_t nfds, int timeout);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __POLL_H__ */
diff --git a/components/libc/compilers/common/sys/time.h b/components/libc/compilers/common/sys/time.h
index c2320429e038e484e54774df0128beb18066e644..9d4422e17a5ab5ac204c93b232d526256e220f54 100644
--- a/components/libc/compilers/common/sys/time.h
+++ b/components/libc/compilers/common/sys/time.h
@@ -8,8 +8,8 @@
  * 2020-09-07     Meco Man     combine gcc armcc iccarm
  * 2021-02-12     Meco Man     move all definitions located in <clock_time.h> to this file
  */
-#ifndef _SYS_TIME_H_
-#define _SYS_TIME_H_
+#ifndef __SYS_TIME_H__
+#define __SYS_TIME_H__
 
 #include <rtconfig.h>
 #include <rtdef.h>
@@ -73,7 +73,7 @@ struct timespec {
 };
 #endif
 
-/* posix clock and timer */
+/* POSIX clock and timer */
 #define MILLISECOND_PER_SECOND  1000UL
 #define MICROSECOND_PER_SECOND  1000000UL
 #define NANOSECOND_PER_SECOND   1000000000UL