diff --git a/trunk/conf/srs.conf b/trunk/conf/srs.conf
index c26ab4cd0..cde87f82f 100755
--- a/trunk/conf/srs.conf
+++ b/trunk/conf/srs.conf
@@ -13,6 +13,8 @@ vhost __defaultVhost__ {
     gop_cache       on;
     hls             on;
     hls_path        ./objs/nginx/html;
+    hls_fragment    10;
+    hls_window      60;
 }
 # the vhost disabled.
 vhost removed.vhost.com {
@@ -39,6 +41,12 @@ vhost no-hls.vhost.com {
     # in a word, the hls_path is for vhost.
     # default: ./objs/nginx/html
     hls_path        /data/nginx/html;
+    # the hls fragment in seconds, the duration of a piece of ts.
+    # default: 10
+    hls_fragment    10;
+    # the hls window in seconds, the number of ts in m3u8.
+    # default: 60
+    hls_window      60;
 }
 # the vhost with hls disabled.
 vhost no-hls.vhost.com {
diff --git a/trunk/src/core/srs_core_client.cpp b/trunk/src/core/srs_core_client.cpp
index 4df02c14c..ee10425c1 100644
--- a/trunk/src/core/srs_core_client.cpp
+++ b/trunk/src/core/srs_core_client.cpp
@@ -332,7 +332,7 @@ int SrsClient::publish(SrsSource* source, bool is_fmle)
 	SrsPithyPrint pithy_print(SRS_STAGE_PUBLISH_USER);
 	
 	// notify the hls to prepare when publish start.
-	if ((ret = source->on_publish(req->vhost, req->stream)) != ERROR_SUCCESS) {
+	if ((ret = source->on_publish(req->vhost, req->app, req->stream)) != ERROR_SUCCESS) {
 		srs_error("hls on_publish failed. ret=%d", ret);
 		return ret;
 	}
diff --git a/trunk/src/core/srs_core_error.hpp b/trunk/src/core/srs_core_error.hpp
index ccb8f1540..dc421a64d 100644
--- a/trunk/src/core/srs_core_error.hpp
+++ b/trunk/src/core/srs_core_error.hpp
@@ -109,7 +109,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #define ERROR_HLS_METADATA				600
 #define ERROR_HLS_DECODE_ERROR			601
-//#define ERROR_HLS_BUSY					602
+#define ERROR_HLS_CREATE_DIR			602
 #define ERROR_HLS_OPEN_FAILED			603
 #define ERROR_HLS_WRITE_FAILED			604
 #define ERROR_HLS_AAC_FRAME_LENGTH		605
diff --git a/trunk/src/core/srs_core_hls.cpp b/trunk/src/core/srs_core_hls.cpp
index 522226dc6..b8020dc20 100644
--- a/trunk/src/core/srs_core_hls.cpp
+++ b/trunk/src/core/srs_core_hls.cpp
@@ -403,12 +403,13 @@ SrsHLS::~SrsHLS()
 	srs_freep(video_frame);
 }
 
-int SrsHLS::on_publish(std::string _vhost, std::string _stream)
+int SrsHLS::on_publish(std::string _vhost, std::string _app, std::string _stream)
 {
 	int ret = ERROR_SUCCESS;
 
 	vhost = _vhost;
 	stream = _stream;
+	app = _app;
 	
 	if ((ret = reopen()) != ERROR_SUCCESS) {
 		return ret;
@@ -555,6 +556,7 @@ int SrsHLS::on_video(SrsSharedPtrMessage* video)
 	if (sample->frame_type == SrsCodecVideoAVCFrameKeyFrame) {
 		int64_t diff = stream_dts - m3u8_dts;
 		// 10s.
+		// TODO: config it.
 		if (diff / 90000 >= 10) {
 			if ((ret = reopen()) != ERROR_SUCCESS) {
 				return ret;
@@ -590,6 +592,11 @@ int SrsHLS::reopen()
 		hls_path = conf->arg0();
 	}
 	
+	// create dir for app.
+	if ((ret = create_dir()) != ERROR_SUCCESS) {
+		return ret;
+	}
+	
 	// start new segment.
 	if (current) {
 		current->duration = (stream_dts - current->segment_start_dts) / 90000.0;
@@ -610,6 +617,8 @@ int SrsHLS::reopen()
 	
 	current->full_path = hls_path;
 	current->full_path += "/";
+	current->full_path += app;
+	current->full_path += "/";
 	current->full_path += filename;
 	
 	// TODO: support base url, and so on.
@@ -619,7 +628,7 @@ int SrsHLS::reopen()
 		srs_error("open hls muxer failed. ret=%d", ret);
 		return ret;
 	}
-	srs_trace("open HLS muxer success. vhost=%s, path=%s", vhost.c_str(), current->full_path.c_str());
+	srs_info("open HLS muxer success. vhost=%s, path=%s", vhost.c_str(), current->full_path.c_str());
 	
 	return ret;
 }
@@ -628,16 +637,33 @@ int SrsHLS::refresh_m3u8()
 {
 	int ret = ERROR_SUCCESS;
 	
+	std::string m3u8_file = hls_path;
+	m3u8_file += "/";
+	m3u8_file += app;
+	m3u8_file += "/";
+	m3u8_file += stream;
+	m3u8_file += ".m3u8";
+	
+	m3u8 = m3u8_file;
+	m3u8_file += ".temp";
+	
 	int fd = -1;
-	ret = _refresh_m3u8(fd);
+	ret = _refresh_m3u8(fd, m3u8_file);
 	if (fd >= 0) {
 		close(fd);
+		if (rename(m3u8_file.c_str(), m3u8.c_str()) < 0) {
+			ret = ERROR_HLS_WRITE_FAILED;
+			srs_error("rename m3u8 file failed. ret=%d", ret);
+		}
 	}
 	
+	// remove the temp file.
+	unlink(m3u8_file.c_str());
+	
 	return ret;
 }
 
-int SrsHLS::_refresh_m3u8(int& fd)
+int SrsHLS::_refresh_m3u8(int& fd, std::string m3u8_file)
 {
 	int ret = ERROR_SUCCESS;
 	
@@ -646,19 +672,14 @@ int SrsHLS::_refresh_m3u8(int& fd)
 		return ret;
 	}
 	
-	m3u8 = hls_path;
-	m3u8 += "/";
-	m3u8 += stream;
-	m3u8 += ".m3u8";
-	
 	int flags = O_CREAT|O_WRONLY|O_TRUNC;
 	mode_t mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH;
-	if ((fd = ::open(m3u8.c_str(), flags, mode)) < 0) {
+	if ((fd = ::open(m3u8_file.c_str(), flags, mode)) < 0) {
 		ret = ERROR_HLS_OPEN_FAILED;
-		srs_error("open m3u8 file %s failed. ret=%d", m3u8.c_str(), ret);
+		srs_error("open m3u8 file %s failed. ret=%d", m3u8_file.c_str(), ret);
 		return ret;
 	}
-	srs_info("open m3u8 file %s success.", m3u8.c_str());
+	srs_info("open m3u8 file %s success.", m3u8_file.c_str());
 	
 	// #EXTM3U\n#EXT-X-VERSION:3\n
 	char header[] = {
@@ -728,11 +749,34 @@ int SrsHLS::_refresh_m3u8(int& fd)
 		}
 		srs_verbose("write m3u8 segment uri success.");
 	}
-	srs_info("write m3u8 %s success.", m3u8.c_str());
+	srs_info("write m3u8 %s success.", m3u8_file.c_str());
 	
 	return ret;
 }
 
+int SrsHLS::create_dir()
+{
+	int ret = ERROR_SUCCESS;
+	
+	std::string app_dir = hls_path;
+	app_dir += "/";
+	app_dir += app;
+	
+	// TODO: cleanup the dir when startup.
+
+	mode_t mode = S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IWGRP|S_IXGRP|S_IROTH|S_IXOTH;
+	if (::mkdir(app_dir.c_str(), mode) < 0) {
+		if (errno != EEXIST) {
+			ret = ERROR_HLS_CREATE_DIR;
+			srs_error("create app dir %s failed. ret=%d", app_dir.c_str(), ret);
+			return ret;
+		}
+	}
+	srs_info("create app dir %s success.", app_dir.c_str());
+
+	return ret;
+}
+
 SrsTSMuxer::SrsTSMuxer()
 {
 	fd = -1;
diff --git a/trunk/src/core/srs_core_hls.hpp b/trunk/src/core/srs_core_hls.hpp
index 6ff684e1d..aed348871 100644
--- a/trunk/src/core/srs_core_hls.hpp
+++ b/trunk/src/core/srs_core_hls.hpp
@@ -72,6 +72,7 @@ class SrsHLS
 private:
 	std::string vhost;
 	std::string stream;
+	std::string app;
 	std::string hls_path;
 private:
 	int file_index;
@@ -103,7 +104,7 @@ public:
 	SrsHLS();
 	virtual ~SrsHLS();
 public:
-	virtual int on_publish(std::string _vhost, std::string _stream);
+	virtual int on_publish(std::string _vhost, std::string _app, std::string _stream);
 	virtual void on_unpublish();
 	virtual int on_meta_data(SrsOnMetaDataPacket* metadata);
 	virtual int on_audio(SrsSharedPtrMessage* audio);
@@ -111,7 +112,8 @@ public:
 private:
 	virtual int reopen();
 	virtual int refresh_m3u8();
-	virtual int _refresh_m3u8(int& fd);
+	virtual int _refresh_m3u8(int& fd, std::string m3u8_file);
+	virtual int create_dir();
 };
 
 class SrsTSMuxer
diff --git a/trunk/src/core/srs_core_source.cpp b/trunk/src/core/srs_core_source.cpp
index 16dc10263..560969eb2 100644
--- a/trunk/src/core/srs_core_source.cpp
+++ b/trunk/src/core/srs_core_source.cpp
@@ -452,9 +452,9 @@ int SrsSource::on_video(SrsCommonMessage* video)
 	return ret;
 }
 
-int SrsSource::on_publish(std::string vhost, std::string stream)
+int SrsSource::on_publish(std::string vhost, std::string app, std::string stream)
 {
-	return hls->on_publish(vhost, stream);
+	return hls->on_publish(vhost, app, stream);
 }
 
 void SrsSource::on_unpublish()
diff --git a/trunk/src/core/srs_core_source.hpp b/trunk/src/core/srs_core_source.hpp
index 62f0bdc1f..b988b140a 100644
--- a/trunk/src/core/srs_core_source.hpp
+++ b/trunk/src/core/srs_core_source.hpp
@@ -166,7 +166,7 @@ public:
 	virtual int on_meta_data(SrsCommonMessage* msg, SrsOnMetaDataPacket* metadata);
 	virtual int on_audio(SrsCommonMessage* audio);
 	virtual int on_video(SrsCommonMessage* video);
-	virtual int on_publish(std::string vhost, std::string stream);
+	virtual int on_publish(std::string vhost, std::string app, std::string stream);
 	virtual void on_unpublish();
 public:
 	virtual int create_consumer(SrsConsumer*& consumer);