vis(1) on FreeBSD
The text ceb54e970ed1, as FreeBSD 6.3-RELEASE, FreeBSD 6.2-RELEASE, FreeBSD 6.1-RELEASE, FreeBSD 6.0-RELEASE shipped it.
display non-printable characters in a visual format
Flags it lists
-
-F -
-b -
-c -
-f -
-l -
-n -
-o -
-s -
-t -
-w