diff --git a/src/algo.cpp b/src/algo.cpp
index 77460ea..e2f64e4 100644
--- a/src/algo.cpp
+++ b/src/algo.cpp
@@ -340,7 +340,7 @@ int Access(const char *filename, int mode){
         if (filename_string.find("data/") == 0)
             full_filename = Header::appledatafolderprefix + filename;
     #endif
-    std::cout << "Access " << full_filename << '\n';
+    std::cout << "Access " << full_filename << std::endl;
     return access(full_filename.c_str(), mode);
 }
 
@@ -353,7 +353,7 @@ CJsonObject ReadJSON(const std::string &filename){
         if (filename.find("data/") == 0)
             full_filename = Header::appledatafolderprefix + filename;
     #endif
-    std::cout << "ReadJSON " << full_filename << '\n';
+    std::cout << "ReadJSON " << full_filename << std::endl;
     auto f = fopen(full_filename.c_str(), "r");
     for (; ; ){
         int length = fread(buffer, 1, JSONBUFFERSIZE - 1, f);
diff --git a/src/main.cpp b/src/main.cpp
index b2bf62c..2f93733 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -50,7 +50,9 @@ namespace MAIN{
             }
             _findclose(findi2);
         #elif defined(__linux) || defined(__APPLE__)
+            std::cout << "try to open: " << dataprefix + "data/" + source << std::endl;
             DIR *dirptr = opendir((dataprefix + "data/" + source).c_str());
+            std::cout << "open success: " << dataprefix + "data/" + source << std::endl;
             dirent *entry;
             while (entry = readdir(dirptr)){
                 ids.push_back(entry -> d_name);