<s>
mcrypt	B-General_Concept
is	O
a	O
replacement	O
for	O
the	O
popular	O
Unix	B-Application
crypt	O
command	O
.	O
</s>
<s>
Mcrypt	B-General_Concept
provides	O
the	O
same	O
functionality	O
but	O
uses	O
several	O
modern	O
algorithms	O
such	O
as	O
AES	B-Algorithm
.	O
</s>
<s>
Libmcrypt	O
,	O
Mcrypt	B-General_Concept
's	O
companion	O
,	O
is	O
a	O
library	O
of	O
code	O
that	O
contains	O
the	O
actual	O
encryption	O
functions	O
and	O
provides	O
an	O
easy	O
method	O
for	O
use	O
.	O
</s>
<s>
These	O
facts	O
have	O
led	O
security	O
experts	O
to	O
declare	O
mcrypt	B-General_Concept
abandonware	O
and	O
discourage	O
its	O
use	O
in	O
new	O
development	O
.	O
</s>
<s>
Maintained	O
alternatives	O
include	O
ccrypt	B-General_Concept
,	O
libressl	B-Language
,	O
and	O
others	O
.	O
</s>
<s>
Examples	O
of	O
mcrypt	B-General_Concept
usage	O
in	O
a	O
Linux	O
command-line	O
environment	O
:	O
</s>
<s>
It	O
implements	O
numerous	O
cryptographic	O
algorithms	O
,	O
mostly	O
block	O
ciphers	O
and	O
stream	B-Algorithm
ciphers	I-Algorithm
,	O
some	O
of	O
which	O
fall	O
under	O
export	O
restrictions	O
in	O
the	O
United	O
States	O
.	O
</s>
<s>
Algorithms	O
include	O
DES	B-Algorithm
,	O
Blowfish	B-Algorithm
,	O
ARCFOUR	B-Algorithm
,	O
Enigma	O
,	O
GOST	B-Algorithm
,	O
LOKI97	B-Algorithm
,	O
RC2	B-Algorithm
,	O
Serpent	B-Algorithm
,	O
Threeway	O
,	O
Twofish	B-Algorithm
,	O
WAKE	B-Algorithm
,	O
and	O
XTEA	B-Algorithm
.	O
</s>
