V8/usr/man/man1/crypt.1

.TH CRYPT 1 
.SH NAME
crypt, encrypt, decrypt \- encode/decode
.SH SYNOPSIS
.B crypt
[ password ]
.PP
.B encrypt
[ password ]
.br
.B decrypt
[ password ]
.SH DESCRIPTION
These commands read from the standard input and write
on the standard output.
The
.I password
is an enciphering key.
If no password
is given,
one is demanded from the terminal;
echoing is turned off while it is being typed in.
.I Crypt
uses a relatively simple, fast method (rotor machine) for both
enciphering and deciphering.
.I Encrypt
and
.I decrypt
use a more robust, slower method (Data Encryption Standard).
Files enciphered by
.I crypt
are compatible with those treated by the editor
.I ed
in encryption mode.
Files enciphered by
.I crypt
are not intelligible to
.I decrypt,
and vice versa.
.PP
It is prudent to supply the key from the terminal,
not from the command line, and to pick a reasonably long
(6 letters) and unobvious key.
Remember, too, that encipherment cannot frustrate
adversaries with super-user privileges.
.SH FILES
/dev/tty for typed key
.SH "SEE ALSO"
ed(1),
makekey(8)
.SH BUGS
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