md5_1.txt

md5的一个校验库

MD5(1)                   USER COMMANDS                     MD5(1)



NAME
     md5 - calculate a message-digest fingerprint (checksum)  for
     a file

SYNOPSIS
     md5 [ -t | -x | -sstring | filename(s) ]

DESCRIPTION
     md5 takes as input a message of arbitrary  length  and  pro-
     duces  as output a 128-bit "fingerprint" or "message digest"
     of the input.  It is conjectured that it is  computationally
     infeasible  to  produce two messages having the same message
     digest, or to produce any message having a  given  prespeci-
     fied  target  message digest.  The MD5 algorithm is intended
     for digital signature applications, where a large file  must
     be  "compressed"  in  a secure manner before being encrypted
     with a private (secret) key under a public-key  cryptosystem
     such as _R_S_A.

OPTIONS
     The following four options may be used in  any  combination,
     except that filename(s) must be the last objects on the com-
     mand line.

     -sstring prints a checksum of the given "string".

     -t runs a built-in time trial.

     -x runs a built-in test script.

     filename(s) prints a checksum(s) for each of the files.

SEE ALSO
     sum(1)

     RFC 1321 describes in detail the MD2, MD4, and MD5  message-
     digest algorithms.

ACKNOWLEDGEMENTS
     This program is placed in the public domain for free general
     use by RSA Data Security.














Sun Release 4.1     Last change: Feb 14, 1994                   1