Cancels a logon dialog by pressing the "Cancel" button.
OraForms.bdh
OraFormsLogonCancel( ) : boolean;
dcltrans 
  transaction TMain 
  begin 
    OraFormsConnect( "server module=module.fmx userid= useSDI=yes"); 
    OraFormsSetWindow( "Logon"); 
    OraFormsLogonCancel(); 
  end TMain;