Deno.seekSync

Synchronously seek a resource ID (rid) to the given offset under mode given by whence. The new position within the resource (bytes from the start) is returned.

const file = Deno.openSync('hello.txt', {read: true, write: true, truncate: true, create: true});
Deno.writeSync(file.rid, new TextEncoder().encode("Hello world"));

// advance cursor 6 bytes
const cursorPosition = Deno.seekSync(file.rid, 6, Deno.SeekMode.Start);
console.log(cursorPosition);  // 6
const buf = new Uint8Array(100);
file.readSync(buf);
console.log(new TextDecoder().decode(buf)); // "world"

The seek modes work as follows:

// Given file.rid pointing to file with "Hello world", which is 11 bytes long:
const file = Deno.openSync('hello.txt', {read: true, write: true, truncate: true, create: true});
Deno.writeSync(file.rid, new TextEncoder().encode("Hello world"));

// Seek 6 bytes from the start of the file
console.log(Deno.seekSync(file.rid, 6, Deno.SeekMode.Start)); // "6"
// Seek 2 more bytes from the current position
console.log(Deno.seekSync(file.rid, 2, Deno.SeekMode.Current)); // "8"
// Seek backwards 2 bytes from the end of the file
console.log(Deno.seekSync(file.rid, -2, Deno.SeekMode.End)); // "9" (e.g. 11-2)
function seekSync(
rid: number,
offset: number,
whence: SeekMode,
): number;
§
seekSync(rid: number, offset: number, whence: SeekMode): number
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§Parameters

§
rid: number
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§
offset: number
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§Return Type

§
number
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