default filepath is now an empty string, SetupWriter will throw an error if path not set (#1133)

Co-authored-by: Dhanya Thattil <dhanya.thattil@psi.ch>

slsReceiverSoftware/src/Implementation.cpp

@@ -919,7 +919,12 @@ void Implementation::CreateUDPSockets() {
 }
 
 void Implementation::SetupWriter() {
+    
     try {
+        //check if filePath empty and throw error
+        if(filePath.empty()){
+            throw ReceiverError("File path cannot be empty");
+        }
         // check if folder exists and throw if it cant create
         mkdir_p(filePath);
         // create first files

slsReceiverSoftware/src/Implementation.h

@@ -314,7 +314,7 @@ class Implementation : private virtual slsDetectorDefs {
 
     // file parameters
     fileFormat fileFormatType{BINARY};
-    std::string filePath{"/"};
+    std::string filePath{};
     std::string fileName{"run"};
     uint64_t fileIndex{0};
     bool fileWriteEnable{false};