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

Usage in Deno

```typescript import { readFileSync } from "node:node__fs.d.ts"; ```
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](../.././node__fs.d.ts/~/readFile). If the `encoding` option is specified then this function returns a string. Otherwise it returns a buffer. Similar to [readFile](../.././node__fs.d.ts/~/readFile), when the path is a directory, the behavior of `fs.readFileSync()` is platform-specific. ```js import { readFileSync } from 'node:fs'; // macOS, Linux, and Windows readFileSync(''); // => [Error: EISDIR: illegal operation on a directory, read ] // FreeBSD readFileSync(''); // => ```

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