diff --git a/client.c b/client.c
index 22a2d5e..09902b6 100644
--- a/client.c
+++ b/client.c
@@ -72,7 +72,7 @@ int main(int argc,char *argv[]) {   //usage: ./client host port
                 FILE *fp = NULL;
                 fp = fopen(buf, "rb");
                 if(fp) {
-                    off_t len;
+                    off_t len = 0;
                     file_size = (uint32_t)fileSize(buf);
                     #if __APPLE__
                         struct iovec headers;
diff --git a/server.c b/server.c
index 782d7ff..ceeaeeb 100644
--- a/server.c
+++ b/server.c
@@ -127,7 +127,7 @@ int sendAll(char* file_path, THREADTIMER *timer) {
         timer->is_open = 1;
         uint32_t file_size = (uint32_t)fileSize(file_path);
         printf("Get file size: %u bytes.\n", file_size);
-        off_t len;
+        off_t len = 0;
         #if __APPLE__
             struct iovec headers;
             headers.iov_base = &file_size;
@@ -136,7 +136,7 @@ int sendAll(char* file_path, THREADTIMER *timer) {
             hdtr.hdr_cnt = 1;
             sendfile(fileno(fp), timer->accept_fd, 0, &len, &hdtr, 0);
         #else
-            //send(timer->accept_fd, &file_size, sizeof(uint32_t), 0);
+            send(timer->accept_fd, &file_size, sizeof(uint32_t), 0);
             sendfile(timer->accept_fd, fileno(fp), &len, file_size);
         #endif
         printf("Send %lld bytes.\n", len);