可写流

可写流是数据写入目标的抽象。

Writable 流的示例包括：

• 客户端上的 HTTP 请求
• 服务器上的 HTTP 响应
• 文件系统写入流
• 压缩流
• 加密流
• TCP 套接字
• 子进程标准输入
• process.stdout、process.stderr

其中一些示例实际上是实现 Writable 接口的 Duplex 流。

所有的 Writable 流都实现了 stream.Writable 类定义的接口。

虽然 Writable 流的特定实例可能以各种方式不同，但所有的 Writable 流都遵循相同的基本使用模式，如下例所示：

const myStream = getWritableStreamSomehow();
myStream.write('some data');
myStream.write('some more data');
myStream.end('done writing data');

Writable streams are an abstraction for a destination to which data is written.

Examples of Writable streams include:

• HTTP requests, on the client
• HTTP responses, on the server
• fs write streams
• zlib streams
• crypto streams
• TCP sockets
• child process stdin
• process.stdout, process.stderr

Some of these examples are actually Duplex streams that implement the Writable interface.

All Writable streams implement the interface defined by the stream.Writable class.

While specific instances of Writable streams may differ in various ways, all Writable streams follow the same fundamental usage pattern as illustrated in the example below:

const myStream = getWritableStreamSomehow();
myStream.write('some data');
myStream.write('some more data');
myStream.end('done writing data');