lib/sync-file.js
function SyncFile(path, flags, mode) {
  flags = flags || 'w';
  this.fd = fs.openSync(path, flags, mode);
  this.crc = new Crc64();
  this.converter = new Converter();
}
function SyncFile(path, flags, mode) {
  flags = flags || 'w';
  this.fd = fs.openSync(path, flags, mode);
  this.crc = new Crc64();
  this.converter = new Converter();
}
Synchronous file writer.