Fixed stupid buglet in avwswapdim

fslswapdim.cc

@@ -52,7 +52,11 @@ int fmrib_main(int argc,char *argv[])
   
   invol.swapdimensions(newx,newy,newz);
 
-  return save_volume4D(invol,outname,volinfo);
+  float retval=0;
+  if (outname!="") {
+    retval = save_volume4D(invol,outname,volinfo);
+  }
+  return retval;
 }