Fix error log

[yardenshoham]

stdout and stderr have the type Uint8Array

[silverwind]

I think TextDecoder would be the better method because that can handle UTF-8 while your current method likely cannot (It seems to only support UTF-16).

const decoder = new TextDecoder();
const decodeToString = (arr: UInt8Array): string => decoder.decode(arr);

Also see https://stackoverflow.com/questions/8936984