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aefp(1)			    General Commands Manual		       aefp(1)

NAME
       aefp - calculate	file fingerprint

SYNOPSIS
       aefp [ option...	 ][ filename...	 ]
       aefp -Help
       aefp -VERSion

DESCRIPTION
       The  aefp  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  <djb@silverton.berkeley.edu>
       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.

OPTIONS
       The following options are understood:

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

       -Identifier
	       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.

       -Help
	       Provide some help with using the	aefp program.

       -Message_Digest
	       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.

       -VERSion
	       Print the version of the	aefp 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 "-project", "-PROJ" and "-p"	are all	inter-
       preted to mean the -Project option.  The	argument "-prj"	 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, after the function selectors.

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

EXIT STATUS
       The aefp	command	will exit with a status	of 1 on	any error.   The  aefp
       command will only exit with a status of 0 if there are no errors.

ENVIRONMENT VARIABLES
       See  aegis(1) for a list	of environment variables which may affect this
       command.	 See aepconf(5)	for the	project	configuration file's project_-
       specific	 field	for  how to set	environment variables for all commands
       executed	by Aegis.

COPYRIGHT
       aefp version 4.25.D510
       Copyright (C) 1991, 1992, 1993, 1994, 1995,  1996,  1997,  1998,	 1999,
       2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011,
       2012 Peter Miller

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

AUTHOR
       Peter Miller   E-Mail:	pmiller@opensource.org.au
       /\/\*		 WWW:	http://miller.emu.id.au/pmiller/

       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 aegis distribution.

Reference Manual		     Aegis			       aefp(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT VARIABLES | COPYRIGHT | AUTHOR

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