Alias of filehandle.writeFile().
When operating on file handles, the mode cannot be changed from what it was set to with fsPromises.open(). Therefore, this is equivalent to filehandle.writeFile().
method
fs.promises.FileHandle.appendFile
data: string | ArrayBufferView<ArrayBufferLike> | Iterable<unknown, any, any> | AsyncIterable<unknown, any, any>,
): Promise<void>;
@returns
Fulfills with undefined upon success.