readFileSync - Node documentation
function readFileSync

Usage in Deno

import { readFileSync } from "node:fs";
readFileSync(
options?: { encoding?: null | undefined; flag?: string | undefined; } | null,
): Buffer

Returns the contents of the path.

For detailed information, see the documentation of the asynchronous version of this API: readFile.

If the encoding option is specified then this function returns a string. Otherwise it returns a buffer.

Similar to readFile, when the path is a directory, the behavior offs.readFileSync() is platform-specific.

import { readFileSync } from 'node:fs';

// macOS, Linux, and Windows
readFileSync('<directory>');
// => [Error: EISDIR: illegal operation on a directory, read <directory>]

//  FreeBSD
readFileSync('<directory>'); // => <data>

Parameters

filename or file descriptor

optional
options: { encoding?: null | undefined; flag?: string | undefined; } | null

Return Type

Buffer
readFileSync(
options: { encoding: BufferEncoding; flag?: string | undefined; } | BufferEncoding,
): string

Synchronously reads the entire contents of a file.

Parameters

A path to a file. If a URL is provided, it must use the file: protocol. If a file descriptor is provided, the underlying file will not be closed automatically.

options: { encoding: BufferEncoding; flag?: string | undefined; } | BufferEncoding

Either the encoding for the result, or an object that contains the encoding and an optional flag. If a flag is not provided, it defaults to 'r'.

Return Type

string
readFileSync(
options?:
(ObjectEncodingOptions & { flag?: string | undefined; })
| BufferEncoding
| null
,
): string | Buffer

Synchronously reads the entire contents of a file.

Parameters

A path to a file. If a URL is provided, it must use the file: protocol. If a file descriptor is provided, the underlying file will not be closed automatically.

optional
options:
(ObjectEncodingOptions & { flag?: string | undefined; })
| BufferEncoding
| null

Either the encoding for the result, or an object that contains the encoding and an optional flag. If a flag is not provided, it defaults to 'r'.

Return Type

string | Buffer