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cookfp(1)		    General Commands Manual		     cookfp(1)

       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  finger-
       print  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  fin-
       gerprint	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  Mes-
	   sage-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.  How-
       ever, 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 perform-
	       ing 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 name.

	       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 op-
       tional.	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	"--op-
       tion=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 er-

       cookfp version 2.30
       Copyright (C) 1988, 1989, 1990, 1991, 1992,  1993,  1994,  1995,	 1996,
       1997,  1998, 1999, 2000,	2001, 2002, 2003, 2004,	2005, 2006, 2007 Peter
       Miller; All rights reserved.

       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.

Reference Manual		     Cook			     cookfp(1)


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