dp_buffer
if (dbg->de_printf_callback.dp_buffer &&
free(dbg->de_printf_callback.dp_buffer);
free(oldval.dp_buffer);
oldval.dp_buffer = 0;
dbg->de_printf_callback.dp_buffer= 0;
dbg->de_printf_callback.dp_buffer =
oldval.dp_buffer;
char * dp_buffer;