foo.tar

foo/000755 000765 000024 00000000000 13467050306 012253 5ustar00isaacsstaff000000 000000 foo/baz.txt000644 000765 000024 00000000004 13467050306 013562 0ustar00isaacsstaff000000 000000 baz
foo/foo.txt000644 000765 000024 00000000004 13467050306 013571 0ustar00isaacsstaff000000 000000 foo
foo/bar.txt000644 000765 000024 00000000004 13467050306 013552 0ustar00isaacsstaff000000 000000 bar

one-file.js

const tar = require('./')
const data = []

const file = 'foo.tar'

const onentry = entry => {
  if (entry.path === 'foo/bar.txt')
    entry.on('data', c => data.push(c))
}

tar.t({
  onentry,
  file,
}, er => {
  const buf = Buffer.concat(data)
  console.log('got the file data', buf.toString('hex'))
})