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       aefp - calculate file fingerprint


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


       The  aefp  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 aefp 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 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
       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  "-project,  "-PROJ"  and  "-p"  are  all
       interpreted  to mean the -Project option.  The argument "-prj" will not
       be  understood,  because  consecutive  optional  characters  were   not

       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
       "--option=value" convention is also understood.


       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.


       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.


       aefp version 4.24.3.D001
       Copyright (C) 1991, 1992, 1993, 1994, 1995,  1996,  1997,  1998,  1999,
       2000,  2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Peter

       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.


       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 aegis distribution.

                               Reference Manual                        aefp(1)