Bug #28366: multiple load_file('a: ... ') causes entire mysqld process to hang

When a Windows console application that has an open console (e.g. mysqld-nt 
started with the --console option) encounters certain type of errors 
(like no floppy disk in a floppy drive) the OS will pop-up an 
"abort/retry/ignore" dialog and block the application (depending on a 
registry setting : see http://msdn2.microsoft.com/en-us/embedded/aa731206.aspx
for details).
Fixed by disabling the dialog popups for every error except a GPF and
alignment errors. This is safe to do as the actual error gets reported
(and handled) to mysqld.

sql/mysqld.cc

@@ -3574,6 +3574,11 @@ we force server id to 2, but this MySQL server will not act as a slave.");
     freopen(log_error_file,"a+",stderr);
     FreeConsole();				// Remove window
   }
+  else
+  {
+    /* Don't show error dialog box when on foreground: it stops the server */ 
+    SetErrorMode(SEM_NOOPENFILEERRORBOX | SEM_FAILCRITICALERRORS);
+  }
 #endif
 
   /*