method Deno.stdin.read
stdin.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"
```
Promise<number | null>