DEBDELTAS(1)							   User Commands						      DEBDELTAS(1)

NAME

       debdeltas - compute deltas between Debian packages

SYNOPSIS

       debdeltas [OPTION]... ARGS ...

DESCRIPTION

       debdeltas computes deltas between the old and new versions of Debian packages.

       The explanation of what a delta is is in debdelta(1).

COMMAND ARGUMENTS

       In  all	of  the  following, ARGS can be, a Debian binary file (usually, a file ending in .deb), or a directory containing such files, or a
       Packages file (that is, an index file such as those found in Debian mirrors - even the zipped ones - see apt-ftparchive(1) ).  We will call
       cmdline all such args that are not related to an option.

       As  a  first  step, debdeltas builds an internal list of Debian packages.  To this end, it parses all  ARGS of the options --alt  , --old ,
       and those ARGS given as non-option arguments (the aforementioned cmdline args). If the argument is a Debian package, debdeltas adds  it	to
       the  list;  if  the  argument  is  a directory, debdeltas scans it for Debian packages to be added to the list; if the argument is Packages
       files, debdeltas parses it and adds all Debian packages to the list.

       Then debdeltas groups all found Debian packages by name and architecture.

       For each group, the newest cmdline version is isolated, and then deltas are computed from all --old versions to that version.

       These deltas are stored in many delta files with appropriate names of the form name_oldversion_newversion_architecture.debdelta ; the loca-
       tion of the delta files is specified by the "--dir" option.

       Note   that   the   location  of  files	in  a  Packages  index	is  specified  relative  to  the  base	of  the  mirror,  e.g.	 Filename:
       pool/main/x/xxx/xxx_3_i386.deb For this reason, any Packages argument must presented with a long path (that contains  at  least	the  dists
       directory).

       Note also that the same directory or index can be provided many times, as --old, as --alt, and as cmdline argument.

       Note also that debdeltas will skip all packages that are smaller than 10KB.

MAIN OPTIONS

       --dir DIR
	      force saving of deltas in this DIR (otherwise they go in the dir of the newer deb_file).

       --alt ARGS
	      this  is parsed as the non-option command line, but the found packages are never considered for a delta.	They are considered though
	      when --clean-deltas is used, to decide if to delete a delta; and are useful to find debs that are deleted  from  indexes	and  moved
	      elsewhere. Multiple --alt can be specified.

       --old ARGS
	      this  is	parsed as the non-option command line, and the found packages are considered as the older versions.  Multiple --old can be
	      specified.  Moreover, when scanning a Packages index, it is not an error if files do not exist, as long as they have been moved in a
	      --alt directory. Note that, if no --old is specified, then no deltas will be generated.

       --forensicdir DIR
	      write hashes files; these are to be compared with those produced by debdelta-upgrade --forensic=...  when a delta fails

The double slash
       If a directory path is provided as argument to --dir, and it ends in // , then this triggers a specific behaviour related to files found in
       Packages indexes (as presented in the commandline). If a package in a index is stored in  pool/main/x/xxx/xxx_3_i386.deb  ,  and  --dir	is
       /tmp/foobar// , then the delta will be saved in /tmp/foobar/pool/main/x/xxx/xxx_2_3_i386.debdelta.  The same is true for --alt (and is use-
       ful to find old versions of a package).

OTHER OPTIONS

       --signing-key  KEY
	      key used to sign the deltas (using GnuPG)

       -n N   how many deltas to produce at maximum for each unique package/arch (default unlimited)

       --clean-deltas
	      delete deltas that upgrade to packages versions that are not found in the cmdline ARGS, and are at least two days old (according	to
	      mtime).

       --no-md5
	      do not include MD5 info in debdelta.

       --needsold
	      create a patch that can only be used if the old .deb is available.

       --delta-algo ALGO
	      use a specific backend for computing binary diffs; possible values are: xdelta xdelta-bzip xdelta3 bsdiff

       -M Mb  maximum memory  to use (for 'bsdiff' or 'xdelta').

       --test check that the patch does apply.

       -v     verbose (can be added multiple times).

       -d     print traceback on errors; save useful info in temporary files in case that a backend crashes.

	      (If '-d' is added multiple times, it also adds to the patches other extra debugging checks: only for advanced bug tracking).

       -k     keep temporary files (use for debugging).

       --gpg-home
	      specify  a different home for GnuPG, default for root is /etc/debdelta/gnupg while for other users is unset. See --homedir in gpg(1)
	      for details.

       --disable-feature FEATURE
	      disable an internal feature. See the documentation in README.features.

       --no-act
	      Just list the deltas that would be created.

SECURITY

       See debdelta(1)

EXIT STATUS

       See debdelta(1)

EXAMPLES

       debdeltas --dir /tmp/ --old ~/mydebs ~/mydebs will generate all deltas to upgrade from the old versions in ~/mydebs to the  newest  version
       in ~/mydebs , and store the deltas in /tmp/

       debdeltas  --dir  /tmp//  --old /mirror/debian/dists/lenny/main/binary-i386/Packages.gz /mirror/debian/dists/squeeze/main/binary-i386/Pack-
       ages.gz will generate all deltas to upgrade main/i386 from lenny to squeeze, and store the deltas in a pool structure under /tmp/

       See also the example scripts /usr/share/debdelta/debmirror-delta-security and /usr/share/debdelta/debmirror-deltas

REPORTING BUGS

       Report bugs to <mennucc1@debian.org>.

AUTHORS

       Debdelta was written and is copyright (C) 2006-09 Andrea Mennucci.
       This man page was written by Jegou Pierre-yves  <pierreyves.jeg@voila.fr>.

COPYING

       This  is  free  software.   You	may  redistribute  copies  of  it  under  the  terms  of  the	GNU   Library	General   Public   License
       <http://www.gnu.org/licenses/lgpl-2.0.html>.  There is NO WARRANTY, to the extent permitted by law.

SEE ALSO

       debpatch(1), debdelta(1), /usr/share/doc/debdelta/README.

debdeltas							     aug 2009							      DEBDELTAS(1)