Skip to main content
Deno.stdin - Deno documentation
variable Deno.stdin
A reference to `stdin` which can be used to read directly from `stdin`. It implements the Deno specific [`Reader`](https://jsr.io/@std/io/doc/types/~/Reader), [`ReaderSync`](https://jsr.io/@std/io/doc/types/~/ReaderSync), and [`Closer`](https://jsr.io/@std/io/doc/types/~/Closer) interfaces as well as provides a `ReadableStream` interface. ### Reading chunks from the readable stream ```ts const decoder = new TextDecoder(); for await (const chunk of Deno.stdin.readable) { const text = decoder.decode(chunk); // do something with the text } ```

Properties

readonly
readable: ReadableStream<Uint8Array>
A readable stream interface to `stdin`.

Methods

read(p: Uint8Array): Promise<number | null>
Read the incoming data from `stdin` into an array buffer (`p`). Resolves to either the number of bytes read during the operation or EOF (`null`) if there was nothing more to read. It is possible for a read to successfully return with `0` bytes. This does not indicate EOF. **It is not guaranteed that the full buffer will be read in a single call.** ```ts // If the text "hello world" is piped into the script: const buf = new Uint8Array(100); const numberOfBytesRead = await Deno.stdin.read(buf); // 11 bytes const text = new TextDecoder().decode(buf); // "hello world" ```
readSync(p: Uint8Array): number | null
Synchronously read from the incoming data from `stdin` into an array buffer (`p`). Returns either the number of bytes read during the operation or EOF (`null`) if there was nothing more to read. It is possible for a read to successfully return with `0` bytes. This does not indicate EOF. **It is not guaranteed that the full buffer will be read in a single call.** ```ts // If the text "hello world" is piped into the script: const buf = new Uint8Array(100); const numberOfBytesRead = Deno.stdin.readSync(buf); // 11 bytes const text = new TextDecoder().decode(buf); // "hello world" ```
close(): void
Closes `stdin`, freeing the resource. ```ts Deno.stdin.close(); ```
setRaw(
mode: boolean,
options?: SetRawOptions,
): void
Set TTY to be under raw mode or not. In raw mode, characters are read and returned as is, without being processed. All special processing of characters by the terminal is disabled, including echoing input characters. Reading from a TTY device in raw mode is faster than reading from a TTY device in canonical mode. ```ts Deno.stdin.setRaw(true, { cbreak: true }); ```
isTerminal(): boolean
Checks if `stdin` is a TTY (terminal). ```ts // This example is system and context specific Deno.stdin.isTerminal(); // true ```