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std/node/_fs/_fs_write.d.ts>write

Deno standard library
denoland/deno_std
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The Standard Library has been moved to JSR. See the blog post for details.
namespace write
import { write } from "https://deno.land/std@0.128.0/node/_fs/_fs_write.d.ts";
function write
import { write } from "https://deno.land/std@0.128.0/node/_fs/_fs_write.d.ts";

Write buffer to the file specified by fd. If buffer is a normal object, it must have an own toString function property.

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

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).

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

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

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

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.

Type Parameters

TBuffer extends ArrayBufferView

Parameters

fd: number
buffer: TBuffer
offset: number | undefined | null
length: number | undefined | null
position: number | undefined | null
callback: (
err: ErrnoException | null,
written: number,
buffer: TBuffer,
) => void

Asynchronously writes buffer to the file referenced by the supplied file descriptor.

Type Parameters

TBuffer extends ArrayBufferView

Parameters

fd: number

A file descriptor.

buffer: TBuffer

The part of the buffer to be written. If not supplied, defaults to 0.

offset: number | undefined | null

The number of bytes to write. If not supplied, defaults to buffer.length - offset.

length: number | undefined | null
callback: (
err: ErrnoException | null,
written: number,
buffer: TBuffer,
) => void

Asynchronously writes buffer to the file referenced by the supplied file descriptor.

Type Parameters

TBuffer extends ArrayBufferView

Parameters

fd: number

A file descriptor.

buffer: TBuffer

The part of the buffer to be written. If not supplied, defaults to 0.

offset: number | undefined | null
callback: (
err: ErrnoException | null,
written: number,
buffer: TBuffer,
) => void

Asynchronously writes buffer to the file referenced by the supplied file descriptor.

Type Parameters

TBuffer extends ArrayBufferView

Parameters

fd: number

A file descriptor.

buffer: TBuffer
callback: (
err: ErrnoException | null,
written: number,
buffer: TBuffer,
) => void

Asynchronously writes string to the file referenced by the supplied file descriptor.

Parameters

fd: number

A file descriptor.

string: string

A string to write.

position: number | undefined | null

The offset from the beginning of the file where this data should be written. If not supplied, defaults to the current position.

encoding: BufferEncoding | undefined | null

The expected string encoding.

callback: (
err: ErrnoException | null,
written: number,
str: string,
) => void

Asynchronously writes string to the file referenced by the supplied file descriptor.

Parameters

fd: number

A file descriptor.

string: string

A string to write.

position: number | undefined | null

The offset from the beginning of the file where this data should be written. If not supplied, defaults to the current position.

callback: (
err: ErrnoException | null,
written: number,
str: string,
) => void

Asynchronously writes string to the file referenced by the supplied file descriptor.

Parameters

fd: number

A file descriptor.

string: string

A string to write.

callback: (
err: ErrnoException | null,
written: number,
str: string,
) => void