Deno Reference for Deno.truncate

function Deno.truncate

allow-write



truncate(name: string,
len?: number,
): Promise<void>

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.writeTextFile(file, "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.

Parameters



name: string

optional



len: number

Return Type

Promise<void>