diff --git a/trunk/src/kernel/srs_kernel_file.cpp b/trunk/src/kernel/srs_kernel_file.cpp
index 194a5e00e..b99259bb7 100644
--- a/trunk/src/kernel/srs_kernel_file.cpp
+++ b/trunk/src/kernel/srs_kernel_file.cpp
@@ -37,11 +37,11 @@ using namespace std;
 #include <srs_kernel_error.hpp>
 
 // For utest to mock it.
-_srs_open_t _srs_open_fn = ::open;
-_srs_write_t _srs_write_fn = ::write;
-_srs_read_t _srs_read_fn = ::read;
-_srs_lseek_t _srs_lseek_fn = ::lseek;
-_srs_close_t _srs_close_fn = ::close;
+srs_open_t _srs_open_fn = ::open;
+srs_write_t _srs_write_fn = ::write;
+srs_read_t _srs_read_fn = ::read;
+srs_lseek_t _srs_lseek_fn = ::lseek;
+srs_close_t _srs_close_fn = ::close;
 
 SrsFileWriter::SrsFileWriter()
 {
diff --git a/trunk/src/kernel/srs_kernel_file.hpp b/trunk/src/kernel/srs_kernel_file.hpp
index b8ed2a15f..46ed18b48 100644
--- a/trunk/src/kernel/srs_kernel_file.hpp
+++ b/trunk/src/kernel/srs_kernel_file.hpp
@@ -121,11 +121,11 @@ public:
 };
 
 // For utest to mock it.
-typedef int (*_srs_open_t)(const char* path, int oflag, ...);
-typedef ssize_t (*_srs_write_t)(int fildes, const void* buf, size_t nbyte);
-typedef ssize_t (*_srs_read_t)(int fildes, void* buf, size_t nbyte);
-typedef off_t (*_srs_lseek_t)(int fildes, off_t offset, int whence);
-typedef int (*_srs_close_t)(int fildes);
+typedef int (*srs_open_t)(const char* path, int oflag, ...);
+typedef ssize_t (*srs_write_t)(int fildes, const void* buf, size_t nbyte);
+typedef ssize_t (*srs_read_t)(int fildes, void* buf, size_t nbyte);
+typedef off_t (*srs_lseek_t)(int fildes, off_t offset, int whence);
+typedef int (*srs_close_t)(int fildes);
 
 #endif
 
diff --git a/trunk/src/kernel/srs_kernel_utility.cpp b/trunk/src/kernel/srs_kernel_utility.cpp
index fb9dd07ff..cd5e27e7d 100644
--- a/trunk/src/kernel/srs_kernel_utility.cpp
+++ b/trunk/src/kernel/srs_kernel_utility.cpp
@@ -125,7 +125,7 @@ srs_utime_t srs_get_system_startup_time()
 
 // For utest to mock it.
 #ifndef SRS_AUTO_OSX
-_srs_gettimeofday_t _srs_gettimeofday = (_srs_gettimeofday_t)::gettimeofday;
+srs_gettimeofday_t _srs_gettimeofday = (srs_gettimeofday_t)::gettimeofday;
 #endif
 
 srs_utime_t srs_update_system_time()
diff --git a/trunk/src/kernel/srs_kernel_utility.hpp b/trunk/src/kernel/srs_kernel_utility.hpp
index c63937430..3c2431f48 100644
--- a/trunk/src/kernel/srs_kernel_utility.hpp
+++ b/trunk/src/kernel/srs_kernel_utility.hpp
@@ -169,7 +169,7 @@ extern int srs_chunk_header_c3(int perfer_cid, uint32_t timestamp, char* cache,
 #ifdef SRS_AUTO_OSX
     #define _srs_gettimeofday gettimeofday
 #else
-    typedef int (*_srs_gettimeofday_t) (struct timeval* tv, struct timezone* tz);
+    typedef int (*srs_gettimeofday_t) (struct timeval* tv, struct timezone* tz);
 #endif
 
 #endif
diff --git a/trunk/src/utest/srs_utest_kernel.cpp b/trunk/src/utest/srs_utest_kernel.cpp
index 7e602b129..43745c1a3 100644
--- a/trunk/src/utest/srs_utest_kernel.cpp
+++ b/trunk/src/utest/srs_utest_kernel.cpp
@@ -3713,11 +3713,11 @@ VOID TEST(KernelFileTest, FileWriteReader)
 }
 
 // Mock the system call hooks.
-extern _srs_open_t _srs_open_fn;
-extern _srs_write_t _srs_write_fn;
-extern _srs_read_t _srs_read_fn;
-extern _srs_lseek_t _srs_lseek_fn;
-extern _srs_close_t _srs_close_fn;
+extern srs_open_t _srs_open_fn;
+extern srs_write_t _srs_write_fn;
+extern srs_read_t _srs_read_fn;
+extern srs_lseek_t _srs_lseek_fn;
+extern srs_close_t _srs_close_fn;
 
 int mock_open(const char* /*path*/, int /*oflag*/, ...) {
 	return -1;
@@ -3742,13 +3742,13 @@ int mock_close(int /*fildes*/) {
 class MockSystemIO
 {
 private:
-	_srs_open_t oo;
-	_srs_write_t ow;
-	_srs_read_t _or;
-	_srs_lseek_t os;
-	_srs_close_t oc;
+	srs_open_t oo;
+	srs_write_t ow;
+	srs_read_t _or;
+	srs_lseek_t os;
+	srs_close_t oc;
 public:
-	MockSystemIO(_srs_open_t o = NULL, _srs_write_t w = NULL, _srs_read_t r = NULL, _srs_lseek_t s = NULL, _srs_close_t c = NULL) {
+	MockSystemIO(srs_open_t o = NULL, srs_write_t w = NULL, srs_read_t r = NULL, srs_lseek_t s = NULL, srs_close_t c = NULL) {
 		oo = _srs_open_fn;
 		ow = _srs_write_fn;
 		os = _srs_lseek_fn;
@@ -4209,7 +4209,7 @@ VOID TEST(KernelUtilityTest, CoverBitsBufferAll)
 }
 
 #ifndef SRS_AUTO_OSX
-extern _srs_gettimeofday_t _srs_gettimeofday;
+extern srs_gettimeofday_t _srs_gettimeofday;
 int mock_gettimeofday(struct timeval* /*tp*/, struct timezone* /*tzp*/) {
 	return -1;
 }
@@ -4217,9 +4217,9 @@ int mock_gettimeofday(struct timeval* /*tp*/, struct timezone* /*tzp*/) {
 class MockTime
 {
 private:
-	_srs_gettimeofday_t ot;
+	srs_gettimeofday_t ot;
 public:
-	MockTime(_srs_gettimeofday_t t = NULL) {
+	MockTime(srs_gettimeofday_t t = NULL) {
 		ot = _srs_gettimeofday;
 		if (t) {
 			_srs_gettimeofday = t;