add an option to musrfit which allows to replace to musrfit_startup.xml by the default one.

src/classes/PStartupHandler.cpp

@@ -91,7 +91,7 @@ int parseXmlFile(TSAXParser *saxParser, const char *startup_path_name)
 /**
  * <p>Constructor. Check if the musrfit_startup.xml file is found in some standard search paths
  */
-PStartupHandler::PStartupHandler()
+PStartupHandler::PStartupHandler(bool reset_startup_file)
 {
   fStartupFileFound = false;
   fStartupFilePath = "";
@@ -145,6 +145,17 @@ PStartupHandler::PStartupHandler()
     }
   }
 
+  // musrfit_startup.xml found. Check if it should be rewritten
+  if (fStartupFileFound && reset_startup_file) {
+    std::cout << std::endl;
+    std::cout << ">> Will only reset the file: '" << fStartupFilePath.Data() << "'."<< std::endl;
+    std::cout << std::endl;
+    if (!WriteDefaultStartupFile(reset_startup_file)) {
+      std::cerr << std::endl << "**ERROR** couldn't re-write " << fStartupFilePath.Data() << "." << std::endl;
+      return;
+    }
+  }
+
   // if musrfit_startup.xml is still not found, will create a default one
   if (!fStartupFileFound) {
     std::cout << std::endl << "**INFO** no musrfit_startup.xml file found, will write a default one." << std::endl;
@@ -606,10 +617,13 @@ Bool_t PStartupHandler::StartupFileExists(Char_t *fln)
 //--------------------------------------------------------------------------
 // WriteDefaultStartupFile
 //--------------------------------------------------------------------------
-Bool_t PStartupHandler::WriteDefaultStartupFile()
+Bool_t PStartupHandler::WriteDefaultStartupFile(bool reset_startup_file)
 {
-  // get home
   Char_t startup_path_name[256];
+  if (reset_startup_file) { // reset the found
+    snprintf(startup_path_name, sizeof(startup_path_name), "%s", fStartupFilePath.Data());
+  } else { // no musrfit_startup.xml found, hence write default under $HOME/.musrfit
+    // get home
     Char_t *home = nullptr;
     home = getenv("HOME");
     if (home == nullptr) {
@@ -633,6 +647,7 @@ Bool_t PStartupHandler::WriteDefaultStartupFile()
 
     // set path-name for musrfit_startup.xml
     snprintf(startup_path_name, sizeof(startup_path_name), "%s/.musrfit/musrfit_startup.xml", home);
+  }
 
   std::ofstream fout(startup_path_name, std::ofstream::out);
   if (!fout.is_open()) {

src/include/PStartupHandler.h

@@ -54,7 +54,7 @@ int parseXmlFile(TSAXParser*, const char*);
 class PStartupHandler : public TObject, public TQObject
 {
   public:
-    PStartupHandler();
+    PStartupHandler(bool reset_startup_file=false);
     virtual ~PStartupHandler();
 
     virtual void OnStartDocument(); // SLOT
@@ -97,7 +97,7 @@ class PStartupHandler : public TObject, public TQObject
     PIntVector           fColorList;        ///< color list
 
     Bool_t StartupFileExists(Char_t *fln);
-    Bool_t WriteDefaultStartupFile();
+    Bool_t WriteDefaultStartupFile(bool reset_startup_file=false);
 
   ClassDef(PStartupHandler, 1)
 };

src/musrfit.cpp

@@ -121,6 +121,12 @@ void musrfit_syntax()
   std::cout << std::endl << "       -u, --use-no-of-threads <number>:";
   std::cout << std::endl << "              <number>: number of threads to be used (OpenMP). Needs to be <= max. number of cores.";
   std::cout << std::endl << "              If OpenMP is enable, the maximal number of cores is used, if it is not limited by this option.";
+  std::cout << std::endl << "       -r, --reset: reset startup musrfit_startup.xml, i.e. rewrite a default, and quit.";
+  std::cout << std::endl << "                    The order of which musrfit_startup.xml is reset is:";
+  std::cout << std::endl << "                       (i)   if present in the current dir.";
+  std::cout << std::endl << "                       (ii)  if present under $HOME/.musrfit/";
+  std::cout << std::endl << "                       (iii) if present under $MUSRFITPATH/";
+  std::cout << std::endl << "                       (iv)  if present under $ROOTSYS/";
   std::cout << std::endl << "       --dump <type> is writing a data file with the fit data and the theory";
   std::cout << std::endl << "              <type> can be 'ascii', 'root'";
   std::cout << std::endl << "       --timeout <timeout_tag>: overwrites to predefined timeout of " << timeout << " (sec).";
@@ -442,6 +448,7 @@ int main(int argc, char *argv[])
   bool chisq_only = false;
   bool title_from_data_file = false;
   bool timeout_enabled = true;
+  bool reset_startup_file = false;
   PStartupOptions startup_options;
   startup_options.writeExpectedChisq = false;
   startup_options.estimateN0 = false;  
@@ -568,6 +575,8 @@ int main(int argc, char *argv[])
         show_syntax = true;
         break;
       }
+    } else if (!strcmp(argv[i], "-r") || !strcmp(argv[i], "--reset")) {
+      reset_startup_file = true;
     } else if (!strcmp(argv[i], "--timeout")) {
       if (i<argc-1) {
         TString str(argv[i+1]);
@@ -595,7 +604,7 @@ int main(int argc, char *argv[])
   }
 
   // check if a filename is present
-  if (strlen(filename) == 0) {
+  if ((strlen(filename) == 0) && !reset_startup_file) {
     show_syntax = true;
     std::cout << std::endl << ">> musrfit **ERROR** no msr-file present!" << std::endl;
   }
@@ -618,7 +627,9 @@ int main(int argc, char *argv[])
   // read startup file
   char startup_path_name[128];
   std::unique_ptr<TSAXParser> saxParser = std::make_unique<TSAXParser>();
-  std::unique_ptr<PStartupHandler> startupHandler = std::make_unique<PStartupHandler>();
+  std::unique_ptr<PStartupHandler> startupHandler = std::make_unique<PStartupHandler>(reset_startup_file);
+  if (reset_startup_file) // only rewrite musrfit_startup.xml has been requested
+    return PMUSR_SUCCESS;
   if (!startupHandler->StartupFileFound()) {
     std::cerr << std::endl << ">> musrfit **WARNING** couldn't find " << startupHandler->GetStartupFilePath().Data();
     std::cerr << std::endl;