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read - node__fs.d.ts - Node documentation
function read

Usage in Deno

```typescript import { read } from "node:node__fs.d.ts"; ```
read<TBuffer extends ArrayBufferView>(
fd: number,
buffer: TBuffer,
offset: number,
length: number,
position: ReadPosition | null,
callback: (
err: ErrnoException | null,
bytesRead: number,
buffer: TBuffer,
) => void
,
): void
Read data from the file specified by `fd`. The callback is given the three arguments, `(err, bytesRead, buffer)`. If the file is not modified concurrently, the end-of-file is reached when the number of bytes read is zero. If this method is invoked as its `util.promisify()` ed version, it returns a promise for an `Object` with `bytesRead` and `buffer` properties.

Type Parameters

TBuffer extends ArrayBufferView

Parameters

fd: number
buffer: TBuffer
The buffer that the data will be written to.
offset: number
The position in `buffer` to write the data to.
length: number
The number of bytes to read.
position: ReadPosition | null
Specifies where to begin reading from in the file. If `position` is `null` or `-1 `, data will be read from the current file position, and the file position will be updated. If `position` is an integer, the file position will be unchanged.
callback: (
err: ErrnoException | null,
bytesRead: number,
buffer: TBuffer,
) => void

Return Type

void
read<TBuffer extends ArrayBufferView>(
fd: number,
options: ReadAsyncOptions<TBuffer>,
callback: (
err: ErrnoException | null,
bytesRead: number,
buffer: TBuffer,
) => void
,
): void
Similar to the above `fs.read` function, this version takes an optional `options` object. If not otherwise specified in an `options` object, `buffer` defaults to `Buffer.alloc(16384)`, `offset` defaults to `0`, `length` defaults to `buffer.byteLength`, `- offset` as of Node 17.6.0 `position` defaults to `null`

Type Parameters

TBuffer extends ArrayBufferView

Parameters

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

Return Type

void
read(
fd: number,
callback: (
err: ErrnoException | null,
bytesRead: number,
buffer: ArrayBufferView,
) => void
,
): void

Parameters

fd: number
callback: (
err: ErrnoException | null,
bytesRead: number,
buffer: ArrayBufferView,
) => void

Return Type

void