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       cookfp - calculate file fingerprint


       cookfp [ option...  ][ filename...  ]
       cookfp -Help
       cookfp -VERSion


       The  cookfp  program is used to calculate the fingerprints of files.  A
       fingerprint is  a  hash  of  the  contents  of  a  file.   The  default
       fingerprint  is  cryptographically  strong,  so  the probability of two
       different files having the same fingerprint is less than 1 in 2**200.

       The fingerprint is based on Dan  Berstien  <>
       public  domain  fingerprint  0.50  beta  package  930809, posted to the
       alt.sources newsgroup.  This program produces  identical  results;  the
       expected test results were generated using Dan’s package.

       The  fingerprint  is a base-64-sanely-encoded fingerprint of the input.
       Imagine this fingerprint  as  something  universal  and  permanent.   A
       fingerprint is 76 characters long, containing the following:

       1.  A  Snefru-8  (version 2.5, 8 passes, 512->256) hash.  (Derived from
           the Xerox Secure Hash Function.)

       2.  An MD5 hash, as  per  RFC  1321.   (Derived  from  the  RSADSI  MD5
           Message-Digest Algorithm.)

       3.  A CRC checksum, as in the new cksum utility.

       4.  Length modulo 2^40.

       The  output  format  is  not  expected  to be compatible with anything.
       However, options are available  to  produce  the  purported  output  of
       Merkle’s  snefru program, the purported output of RSADSI’s mddriver -x,
       or the purported output of the POSIX cksum program.

       If no files are named as input, the standard input will be  used.   The
       special file name ‘‘-’’ is understood to mean the standard input.


       The following options are understood:

               Print the CRC32 checksum and length of the named file(s).

               Print   a  condensed  form  of  the  fingerprint  (obtained  by
               performing a CRC32 checksum on the full  fingerprint  described
               above  -  a definite overkill).  This is an 8-digit hexadecimal
               number, useful for generating unique short identifiers  out  of
               long  names.   The first character is forced to be a letter (g-
               p), so there is no problem in using the output  as  a  variable

               Provide some help with using the cookfp program.

               Print  the RSA Data Security, Inc. MD5 Message-Digest Algorithm
               hash of the named file(s).

       -Snefru Print the Snefru hash of the named file(s),  derived  from  the
               Xerox Secure Hash Function.

               Print the version of the cookfp program being executed.

       All other options will produce a diagnostic error.

       All  options  may be abbreviated; the abbreviation is documented as the
       upper case letters, all lower case  letters  and  underscores  (_)  are
       optional.  You must use consecutive sequences of optional letters.

       All  options  are  case insensitive, you may type them in upper case or
       lower case or a combination of both, case is not important.

       For example: the arguments "-help", "-HEL" and "-h" are all interpreted
       to  mean the -Help option.  The argument "-hlp" will not be understood,
       because consecutive optional characters were not supplied.

       Options and other command line arguments may be  mixed  arbitrarily  on
       the command line.

       The  GNU  long option names are understood.  Since all option names for
       cookfp are long, this  means  ignoring  the  extra  leading  ’-’.   The
       "--option=value" convention is also understood.


       The  cookfp  command  will  exit  with a status of 1 on any error.  The
       cookfp command will only exit with a  status  of  0  if  there  are  no


       cookfp version 2.33
       Copyright  (C)  1988,  1989,  1990, 1991, 1992, 1993, 1994, 1995, 1996,
       1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
       2009 Peter Miller

       The  cookfp  program comes with ABSOLUTELY NO WARRANTY; for details use
       the ’cookfp -VERSion License’ command.  This is free software  and  you
       are  welcome  to  redistribute it under certain conditions; for details
       use the ’cookfp -VERSion License’ command.


       Peter Miller   E-Mail:
       /\/\*             WWW:

       Portions of this program are derived from sources  from  other  people,
       sometimes  with liberal copyrights, and sometimes in the public domain.
       These include:

       Dan Bernstien
               See common/fp/README for details.

       Gary S Brown.
               See common/fp/crc32.c for details.

       RSA Data Security, Inc.
               See common/fp/md5.c for details.

       Xerox Corporation
               See common/fp/snefru.c for details.

       In addition to the above copyright holders, there  have  been  numerous
       authors and contributors, see the named files for details.  Files names
       are relative to the root of the cook distribution.