fs.write(fd, buffer, offset[, length[, position]], callback)

• fd <integer>

• buffer <Buffer> | <TypedArray> | <DataView>

• offset <integer> 默认值：0

  ¥offset <integer> Default: 0

• length <integer> 默认值：buffer.byteLength - offset

  ¥length <integer> Default: buffer.byteLength - offset

• position <integer> | <null> 默认值：null

  ¥position <integer> | <null> Default: null

• callback <Function>

  • err <Error>

  • bytesWritten <integer>

  • buffer <Buffer> | <TypedArray> | <DataView>

将 buffer 写入 fd 指定的文件。

¥Write buffer to the file specified by fd.

offset 确定要写入的缓冲区部分，length 是整数，指定要写入的字节数。

¥offset determines the part of the buffer to be written, and length is an integer specifying the number of bytes to write.

position 指从文件开头数据应被写入的偏移量。如果 typeof position !== 'number'，则数据将写入当前位置。请参见 pwrite(2)。

¥position refers to the offset from the beginning of the file where this data should be written. If typeof position !== 'number', the data will be written at the current position. See pwrite(2).

回调将被赋予三个参数 (err, bytesWritten, buffer)，其中 bytesWritten 指定从 buffer 写入了多少字节。

¥The callback will be given three arguments (err, bytesWritten, buffer) where bytesWritten specifies how many bytes were written from buffer.

如果此方法作为其 util.promisify() 版本被调用，则返回具有 bytesWritten 和 buffer 属性的 Object 的 promise。

¥If this method is invoked as its util.promisify()ed version, it returns a promise for an Object with bytesWritten and buffer properties.

在同一个文件上多次使用 fs.write() 而不等待回调是不安全的。对于这种情况，建议使用 fs.createWriteStream()。

¥It is unsafe to use fs.write() multiple times on the same file without waiting for the callback. For this scenario, fs.createWriteStream() is recommended.

在 Linux 上，以追加模式打开文件时，位置写入不起作用。内核会忽略位置参数，并始终将数据追加到文件末尾。

¥On Linux, positional writes don't work when the file is opened in append mode. The kernel ignores the position argument and always appends the data to the end of the file.