unvis —
revert a visual representation of data back to original
  form
  
    | unvis | [ -e] [-Hh|-m] [file ...] | 
unvis is the inverse function of
  vis(1). It reverts a visual
  representation of data back to its original form on standard output.
The options are as follows:
  - -e
- Don't decode \ escaped sequences.
- -H
- Decode entity references and numeric character references from RFC 1866.
      (VIS_HTTP1866)
- -h
- Decode using the URI encoding from RFC 1808.
      (VIS_HTTP1808)
- -m
- Decode using mime style. (VIS_MIMESTYLE)
Mixing -h or -H
    with -m is not supported.
The unvis command appears in
  4.4BSD.