writeStream.path

流正在写入的文件的路径，如 fs.createWriteStream() 的第一个参数中所指定。 如果 path 作为字符串传入，则 writeStream.path 将是字符串。 如果 path 作为 <Buffer> 传入，则 writeStream.path 将是 <Buffer>。

The path to the file the stream is writing to as specified in the first argument to fs.createWriteStream(). If path is passed as a string, then writeStream.path will be a string. If path is passed as a <Buffer>, then writeStream.path will be a <Buffer>.