diff --git a/trunk/configure b/trunk/configure
index 7d87945e3..29076aa84 100755
--- a/trunk/configure
+++ b/trunk/configure
@@ -82,7 +82,7 @@ LibSTfile="${LibSTRoot}/libst.a"
 MODULE_ID="CORE" 
 MODULE_DEPENDS=() 
 ModuleLibIncs=(${LibSTRoot})
-MODULE_FILES=("srs_core_log")
+MODULE_FILES=("srs_core" "srs_core_log")
 MODULE_DIR="src/core" . auto/modules.sh
 CORE_OBJS="${MODULE_OBJS[@]}"
 
diff --git a/trunk/src/core/srs_core.cpp b/trunk/src/core/srs_core.cpp
new file mode 100755
index 000000000..21d7f9cba
--- /dev/null
+++ b/trunk/src/core/srs_core.cpp
@@ -0,0 +1 @@
+#include <srs_core.hpp>
diff --git a/trunk/src/core/srs_core.hpp b/trunk/src/core/srs_core.hpp
index 1275a4cb1..aa432e3e2 100755
--- a/trunk/src/core/srs_core.hpp
+++ b/trunk/src/core/srs_core.hpp
@@ -5,6 +5,8 @@
 #include <srs_core.hpp>
 */
 
+// user must include the srs_core.hpp before any header.
+
 // for int64_t print using PRId64 format.
 #ifndef __STDC_FORMAT_MACROS
     #define __STDC_FORMAT_MACROS
diff --git a/trunk/src/core/srs_core_log.hpp b/trunk/src/core/srs_core_log.hpp
index 8a35d763e..df3635aaf 100755
--- a/trunk/src/core/srs_core_log.hpp
+++ b/trunk/src/core/srs_core_log.hpp
@@ -12,6 +12,7 @@
 #include <errno.h>
 #include <string.h>
 
+// the context for multiple clients.
 class ILogContext
 {
 public:
diff --git a/trunk/src/upp/upp.upp b/trunk/src/upp/upp.upp
index 3786c3477..bff429b9f 100755
--- a/trunk/src/upp/upp.upp
+++ b/trunk/src/upp/upp.upp
@@ -3,6 +3,7 @@ file
     ..\main\srs_main_server.cpp,
 	core readonly separator,
     ..\core\srs_core.hpp,
+    ..\core\srs_core.cpp,
     ..\core\srs_core_log.hpp,
     ..\core\srs_core_log.cpp;
 mainconfig