filehandle.write(buffer, offset[, length[, position]])

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

• offset <integer> 要开始写入数据的 buffer 的起始位置。

  ¥offset <integer> The start position from within buffer where the data to write begins.

• length <integer> 要从 buffer 写入的字节数。默认值：buffer.byteLength - offset

  ¥length <integer> The number of bytes from buffer to write. Default: buffer.byteLength - offset

• position <integer> | <null> 要写入来自 buffer 的数据的文件的开头偏移量。如果 position 不是 number，则数据将被写入当前位置。有关更多详细信息，请参阅 POSIX pwrite(2) 文档。默认值：null

  ¥position <integer> | <null> The offset from the beginning of the file where the data from buffer should be written. If position is not a number, the data will be written at the current position. See the POSIX pwrite(2) documentation for more detail. Default: null

• 返回：<Promise>

  ¥Returns: <Promise>

将 buffer 写入文件。

¥Write buffer to the file.

这个 promise 是通过一个包含两个属性的对象来实现的：

¥The promise is fulfilled with an object containing two properties:

• bytesWritten <integer> 写入的字节数

  ¥bytesWritten <integer> the number of bytes written

• buffer <Buffer> | <TypedArray> | <DataView> 对被写入的 buffer 的引用。

  ¥buffer <Buffer> | <TypedArray> | <DataView> a reference to the buffer written.

在同一个文件上多次使用 filehandle.write() 而不等待 promise 被履行（或拒绝）是不安全的。对于这种情况，请使用 filehandle.createWriteStream()。

¥It is unsafe to use filehandle.write() multiple times on the same file without waiting for the promise to be fulfilled (or rejected). For this scenario, use filehandle.createWriteStream().

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 do not 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.