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 withinbuffer
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 frombuffer
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 POSIXpwrite(2)
文档。默认值:null
¥
position
<integer> | <null> The offset from the beginning of the file where the data frombuffer
should be written. Ifposition
is not anumber
, the data will be written at the current position. See the POSIXpwrite(2)
documentation for more detail. Default:null
-
返回:<Promise>
¥Returns: <Promise>
将 buffer
写入文件。
¥Write buffer
to the file.
使用包含以下两个属性的对象来解决 promise:
¥The promise is resolved 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 thebuffer
written.
在同一文件上多次使用 filehandle.write()
而不等待 promise 被解决(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 resolved (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.