Example Ttdt_file_cb

Example D-2 is an example of a typical algorithm of this callback.

Example D-2 Typical Algorithm of Ttdt_file_cb

Tt_message myFileCB(
         Tt_message      msg,
         Tttk_op         op,
         char           *pathname,
         int             trust,
         int             isMe 
) 
{
         tt_free( pathname );
         Tt_status status = TT_OK;
         switch (op) {
             case TTDT_MODIFIED:
                 if ((_modifiedByMe) && (! isMe)) {
                         // Hmm, the other editor either does not know or
                         // does not care that we are already modifying the
                         // file, so the last saver will win.
                 } else {
                         // Interrogate user if she ever modifies the buffer
                         _modifiedByOther = 1;
                         XtAddCallback( myTextWidget, XmNmodifyVerifyCallback,
                                        myTextModifyCB, 0 );
                 }
                 break;
             case TTDT_GET_MODIFIED:
                 tt_message_arg_ival_set( msg, 1, _modifiedByMe );
                 tt_message_reply( msg );
                 break;
             case TTDT_SAVE:
                 status = mySave( trust );
                 if (status == TT_OK) {
                         tt_message_reply( msg );
                 } else {
                         tttk_message_fail( msg, status, 0, 0 );
                 }                 break;
             case TTDT_REVERT:
                 status = myRevert( trust );
                 if (status == TT_OK) {
                         tt_message_reply( msg );
                 } else {
                         tttk_message_fail( msg, status, 0, 0 );
                 }
                 break;
             case TTDT_REVERTED:
                 if (! isMe) {
                         _modifiedByOther = 0;
                 }
                 break;
             case TTDT_SAVED:
                 if (! isMe) {
                         _modifiedByOther = 0;
                         int choice = myUserChoice( myContext, myBaseFrame,
                                                  "Another tool has saved "
                                                  "this file.", 2, "Ignore",
                                                  "Revert" );
                         switch (choice) {
                             case 1:
                                 myRevert( 1 );
                                 break;
                         }
                 }
                 break;
             case TTDT_MOVED:
             case TTDT_DELETED:
                 // Do something appropriate
                 break;
         }
         tttk_message_destroy( msg );
         return 0; 
}