added a feature which brings up a error message box, if there was any issue with the msr-file when starting musrview from musredit.

src/musrview.cpp

@@ -38,6 +38,8 @@
 #include <iostream>
 #include <memory>
 #include <vector>
+#include <sstream>
+
 
 #include <TApplication.h>
 #include <TSAXParser.h>
@@ -53,6 +55,7 @@
 #include "PRunDataHandler.h"
 #include "PRunListCollection.h"
 #include "PMusrCanvas.h"
+#include "PMsgBox.h"
 
 
 //--------------------------------------------------------------------------
@@ -81,9 +84,21 @@ void musrview_syntax()
   std::cout << std::endl << "           will produce an ascii dump of the data and fit as plotted.";
   std::cout << std::endl << "       --timeout <timeout>: <timeout> given in seconds after which musrview terminates.";
   std::cout << std::endl << "           If <timeout> <= 0, no timeout will take place. Default <timeout> is 0.";
+  std::cout << std::endl << "       -s, --show-errMsgBox: if this tag is defined, error message boxes are shown,";
+  std::cout << std::endl << "                             rather than only stderr output.";
   std::cout << std::endl << std::endl;
 }
 
+//--------------------------------------------------------------------------
+void musrview_error_msg(std::string errMsg)
+{
+  int argc=0; 
+  char **argv;
+  TApplication app("musrviewErrorMsg", &argc, argv);
+  new PMsgBox(errMsg, gClient->GetRoot(), 600, 200);
+  app.Run();
+}
+
 //--------------------------------------------------------------------------
 /**
  * <p>The musrview program is used to show muSR fit results in graphical form.
@@ -104,18 +119,20 @@ void musrview_syntax()
  */
 int main(int argc, char *argv[])
 {
-  int result = PMUSR_SUCCESS;
-  bool show_syntax = false;
+  int result{PMUSR_SUCCESS};
+  bool show_syntax{false};
   int  status;
-  bool success = true;
+  bool success{true};
   char fileName[128];
-  bool fourier = false;
-  bool avg = false;
-  bool theoAtData = false; // theory points only at data points
-  bool graphicsOutput = false;
-  bool asciiOutput = false;
+  bool fourier{false};
+  bool avg{false};
+  bool theoAtData{false}; // theory points only at data points
+  bool graphicsOutput{false};
+  bool asciiOutput{false};
   char graphicsExtension[128];
-  int  timeout = 0;
+  int  timeout{0};
+  bool show_errMsgBox{false};
+  std::stringstream errMsg;
 
   memset(fileName, '\0', sizeof(fileName));
 
@@ -188,6 +205,8 @@ int main(int argc, char *argv[])
         show_syntax = true;
         break;
       }
+    } else if (!strcmp(argv[i], "-s") || !strcmp(argv[i], "--show-errMsgBox")) {
+      show_errMsgBox = true;
     } else {
       show_syntax = true;
       break;
@@ -227,17 +246,24 @@ int main(int argc, char *argv[])
   std::unique_ptr<PMsrHandler> msrHandler = std::make_unique<PMsrHandler>(fileName);
   status = msrHandler->ReadMsrFile();
   if (status != PMUSR_SUCCESS) {
+    errMsg << msrHandler->GetLastErrorMsg();
     switch (status) {
       case PMUSR_MSR_FILE_NOT_FOUND:
-        std::cerr << std::endl << ">> musrview **ERROR** couldn't find '" << fileName << "'" << std::endl << std::endl;
+        errMsg << "\n";
+        errMsg << ">> musrview **ERROR** couldn't find '" << fileName << "'\n\n";
         break;
       case PMUSR_MSR_SYNTAX_ERROR:
-        std::cerr << std::endl << ">> musrview **SYNTAX ERROR** in file " << fileName << ", full stop here." << std::endl << std::endl;
+        errMsg << "\n";
+        errMsg << ">> musrview **SYNTAX ERROR** in file " << fileName << ", full stop here.\n\n";
         break;
       default:
-        std::cerr << std::endl << ">> musrview **UNKNOWN ERROR** when trying to read the msr-file" << std::endl << std::endl;
+        errMsg << "\n";
+        errMsg << ">> musrview **UNKNOWN ERROR** when trying to read the msr-file.\n\n";
         break;
     }
+    std::cerr << errMsg.str();
+    if (show_errMsgBox)
+      musrview_error_msg(errMsg.str());
     return status;
   }
   // make a plot list vector