Added switch to disable verbose exit codes.

In the near future, the default exit code behavior should be made obsolete anyway,
as the exit codes are not a nice way to report status.
It used to be convenient for shell scripting in early times,
when the parallel tests were run using the forward model
checker, but no modern script should be relying on it.

src/main.c

@@ -234,7 +234,14 @@ main (int argc, char **argv)
   /* memory clean up? */
   strings_cleanup ();
 
-  return exitcode;
+  if (switches.exitCodes)
+    {
+      return exitcode;
+    }
+  else
+    {
+      return 0;
+    }
 }
 
 //! Analyse the model

src/switches.c

@@ -108,6 +108,7 @@ switchesInit (int argc, char **argv)
   switches.monochrome = false;	// default colors for dot
   switches.lightness = 0;	// lightness correction
   switches.clusters = false;	// default is no clusters for now
+  switches.exitCodes = true;	// default is to flag exit codes
 
   // Process the environment variable SCYTHERFLAGS
   process_environment ();
@@ -900,6 +901,22 @@ switcher (const int process, int index, int commandline)
 	}
     }
 
+  if (detect (' ', "no-exitcodes", 0))
+    {
+      if (!process)
+	{
+	  if (switches.expert)
+	    {
+	      helptext ("    --no-exitcodes", "Disable verbose exitcodes.");
+	    }
+	}
+      else
+	{
+	  switches.exitCodes = false;
+	  return index;
+	}
+    }
+
 
   /* ==================
    *  Modelchecker only

src/switches.h

@@ -83,7 +83,8 @@ struct switchdata
   int plain;			//!< Disable color output on terminal
   int monochrome;		//!< Disable colors in dot output
   int lightness;		//!< Lightness increment 0-100
-  int clusters;			//!> Enable clusters in output
+  int clusters;			//!< Enable clusters in output
+  int exitCodes;		//!< Enable verbose exit codes
 };
 
 extern struct switchdata switches;	//!< pointer to switchdata structure