function copyBinaryFile(srcPath, destPath, cb) {
  let cbCalled = false;
  const srcPermissions = fs.statSync(srcPath).mode;
  const readStream = fs.createReadStream(srcPath);
  readStream.on('error', function(err) {
    done(err);
  });
  const writeStream = fs.createWriteStream(destPath, {
    mode: srcPermissions
  });
  writeStream.on('error', function(err) {
    done(err);
  });
  writeStream.on('close', function(ex) {
    done();
  });
  readStream.pipe(writeStream);
  function done(err) {
    if (!cbCalled) {
      cb(err);
      cbCalled = true;
    }
  }
}
Same as 'cp' on Unix. Don't do any replacements.