def self.from(stream)
header = stream.read 512
empty = (header == "\0" * 512)
fields = header.unpack UNPACK_FORMAT
name = fields.shift
mode = fields.shift.oct
uid = fields.shift.oct
gid = fields.shift.oct
size = fields.shift.oct
mtime = fields.shift.oct
checksum = fields.shift.oct
typeflag = fields.shift
linkname = fields.shift
magic = fields.shift
version = fields.shift.oct
uname = fields.shift
gname = fields.shift
devmajor = fields.shift.oct
devminor = fields.shift.oct
prefix = fields.shift
new :name => name,
:mode => mode,
:uid => uid,
:gid => gid,
:size => size,
:mtime => mtime,
:checksum => checksum,
:typeflag => typeflag,
:linkname => linkname,
:magic => magic,
:version => version,
:uname => uname,
:gname => gname,
:devmajor => devmajor,
:devminor => devminor,
:prefix => prefix,
:empty => empty
end