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 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  <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 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.

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 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 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  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 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 "--option=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 4.24.3.D001
       Copyright  (C)  1991,  1992,  1993,  1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
       2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Peter 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:   millerp@canb.auug.org.au
       /\/\*             WWW:   http://www.canb.auug.org.au/~millerp/

       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)