appendFile - fs/promises - Node

function appendFile

Usage in Deno

import { appendFile } from "node:fs/promises";



appendFile(path: PathLike | FileHandle,
data: string | Uint8Array,
options?: (ObjectEncodingOptions
 & FlagAndOpenMode
 & { flush?: boolean | undefined;  }
)
 | BufferEncoding
 | null,
): Promise<void>

Asynchronously append data to a file, creating the file if it does not yet exist. data can be a string or a Buffer.

If options is a string, then it specifies the encoding.

The mode option only affects the newly created file. See fs.open() for more details.

The path may be specified as a FileHandle that has been opened for appending (using fsPromises.open()).

Parameters



path: PathLike | FileHandle

filename or {FileHandle}



data: string | Uint8Array

optional



options: (ObjectEncodingOptions
 & FlagAndOpenMode
 & { flush?: boolean | undefined;  }
)
 | BufferEncoding
 | null

Return Type

Promise<void>

Fulfills with undefined upon success.