void on_stdout_write(uv_write_t *req, int status) { free_write_req(req); }
void on_file_write(uv_write_t *req, int status) { free_write_req(req); }
void write_cb(uv_write_t* req, int status) { assert(status == 0); assert(req->type == UV_WRITE); free_write_req(req); }