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

Usage in Deno

```typescript import { watch } from "node:node__fs.d.ts"; ```
watch(
filename: PathLike,
options: (WatchOptions & { encoding: "buffer"; }) | "buffer",
listener?: WatchListener<Buffer>,
): FSWatcher
Watch for changes on `filename`, where `filename` is either a file or a directory. The second argument is optional. If `options` is provided as a string, it specifies the `encoding`. Otherwise `options` should be passed as an object. The listener callback gets two arguments `(eventType, filename)`. `eventType`is either `'rename'` or `'change'`, and `filename` is the name of the file which triggered the event. On most platforms, `'rename'` is emitted whenever a filename appears or disappears in the directory. The listener callback is attached to the `'change'` event fired by `fs.FSWatcher`, but it is not the same thing as the `'change'` value of `eventType`. If a `signal` is passed, aborting the corresponding AbortController will close the returned `fs.FSWatcher`.

Parameters

filename: PathLike
options: (WatchOptions & { encoding: "buffer"; }) | "buffer"
optional
listener: WatchListener<Buffer>

Return Type

watch(
filename: PathLike,
options?:
WatchOptions
| BufferEncoding
| null
,
listener?: WatchListener<string>,
): FSWatcher
Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.

Parameters

filename: PathLike
A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
optional
options:
WatchOptions
| BufferEncoding
| null
Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options. If `encoding` is not supplied, the default of `'utf8'` is used. If `persistent` is not supplied, the default of `true` is used. If `recursive` is not supplied, the default of `false` is used.
optional
listener: WatchListener<string>

Return Type

watch(
filename: PathLike,
options: WatchOptions | string,
listener?: WatchListener<string | Buffer>,
): FSWatcher
Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.

Parameters

filename: PathLike
A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
options: WatchOptions | string
Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options. If `encoding` is not supplied, the default of `'utf8'` is used. If `persistent` is not supplied, the default of `true` is used. If `recursive` is not supplied, the default of `false` is used.
optional
listener: WatchListener<string | Buffer>

Return Type

watch(
filename: PathLike,
listener?: WatchListener<string>,
): FSWatcher
Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.

Parameters

filename: PathLike
A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
optional
listener: WatchListener<string>

Return Type