Ttmedia_load_pat_cb の例

例 D-4 は、このコールバックの典型的なアルゴリズムの例です。

例 D-4 TTtmedia_load_pat_cb の典型的なアルゴリズム

Tt_message 
myAcmeSheetLoadCB(
    Tt_message      msg,
    void            *client_data,
    Tttk_op         op,
    Tt_status       diagnosis,
    unsigned char   *contents,
    int             len,
    char            *file,
    char            *docname 
) 
{
    Tt_status status = TT_OK;
    if (diagnosis != TT_OK) {
      // toolkit detected an error
      if (tt_message_status( msg ) == TT_WRN_START_MESSAGE) {
        //
        // Error is in start message!    We now have no
        // reason to live, so tell main() to exit().
        //
        myAbortCode = 2;
      }
      // let toolkit handle the error
      return msg;
    }
    if ((op == TTME_COMPOSE) && (file == 0)) {
      // open empty new buffer
    } else if (len > 0) {
      // load contents into new buffer
    } else if (file != 0) {
      if (ttdt_Get_Modified( msg, file, TT_BOTH, myCntxt, 5000 )) {
        switch (myUserChoice( "Save, Revert, Ignore?" )) {
          case 0:
            ttdt_Save( msg, file, TT_BOTH, myCntxt, 5000 );
            break;
          case 1:
            ttdt_Revert( msg, file, TT_BOTH, myCntxt, 5000);
            break;
        }
      }
        // load file into new buffer
    } else {
      tttk_message_fail( msg, TT_DESKTOP_ENODATA, 0, 1 );
      tt_free( contents ); tt_free( file ); tt_free( docname );
      return 0;
    }
    int w, h, x, y = INT_MAX;
    ttdt_sender_imprint_on( 0, msg, 0, &w, &h, &x, &y, myCntxt, 5000 );
    positionMyWindowRelativeTo( w, h, x, y );
    if (maxBuffersAreNowOpen) {
      // Un-volunteer to handle future requests until less busy
      tt_ptype_undeclare( "Acme_Calc" );
    }
    if (tt_message_status( msg ) == TT_WRN_START_MESSAGE) {
      //
      // Join session before accepting start message,
      // to prevent unnecessary starts of our ptype
      // 
      ttdt_session_join( 0, myContractCB, myShell, 0, 1 );
    }
    ttdt_message_accept( msg, myContractCB, myShell, 0, 1, 1 );
    tt_free( contents ); tt_free( file ); tt_free( docname );
    return 0;
}