import { Deno } from "https://deno.land/x/levo@v0.0.27/lib/lib.deno_runtime.d.ts";
const { truncate } = Deno;
Truncates or extends the specified file, to reach the specified len. If
len is not specified then the entire file contents are truncated.
// truncate the entire file
await Deno.truncate("my_file.txt");
// truncate part of the file
const file = await Deno.makeTempFile();
await Deno.writeFile(file, new TextEncoder().encode("Hello World"));
await Deno.truncate(file, 7);
const data = await Deno.readFile(file);
console.log(new TextDecoder().decode(data)); // "Hello W"
Requires allow-write permission.