Gem::Package::TarWriter#add_symlink

# File tmp/rubies/ruby-3.3.0/lib/rubygems/package/tar_writer.rb, line 233
def add_symlink(name, target, mode)
  check_closed

  name, prefix = split_name name

  header = Gem::Package::TarHeader.new(name: name, mode: mode,
                                       size: 0, typeflag: "2",
                                       linkname: target,
                                       prefix: prefix,
                                       mtime: Gem.source_date_epoch).to_s

  @io.write header

  self
end