function Deno.read
Read from a resource ID (rid
) into an array buffer (buffer
).
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.
This function is one of the lowest level APIs and most users should not
work with this directly, but rather use ReadableStream
and
|toArrayBuffer
| https://deno.land/std/streams/mod.ts?s=toArrayBuffer
instead.
It is not guaranteed that the full buffer will be read in a single call.
// if "/foo/bar.txt" contains the text "hello world":
const file = await Deno.open("/foo/bar.txt");
const buf = new Uint8Array(100);
const numberOfBytesRead = await Deno.read(file.rid, buf); // 11 bytes
const text = new TextDecoder().decode(buf); // "hello world"
Deno.close(file.rid);
Return Type
🔗
Promise<number | null>