How to use

copy

function

in

Array

function encode(command, status, transaction, data = []) {
 const buffer = Buffer.allocUnsafe(4 + data.length);
 buffer.writeUInt8(command, 0);
 buffer.writeUInt8(status, 1);
 buffer.writeUInt16LE(transaction, 2);
 if (data.length > 0) {
  data.copy(buffer, 4);
 }
 return buffer;
}

Object.keys(fileHeader).forEach(function (filePath) {
  let meta = fileHeader[filePath]
  let fileBuffer = new Buffer(meta.size)
  let readSize = project.copy(fileBuffer, 0, pos + meta.offset, pos + meta.offset + meta.size)
  if (readSize !== meta.size) throw new Error(`unable to unlock ${filePath}.`)

  let content
  if (!meta.stat.isFile) content = null
  else if (meta.stat.isBinary) content = new Buffer(fileBuffer.toString(), 'hex')
  else content = decrypt(fileBuffer, key)

  filesMap.set(path.resolve(process.cwd(), filePath), {
   stat: formatStat(meta.stat),
   content
  })
 })