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DACT(1)			    General Commands Manual		       DACT(1)

NAME
       dact - compress or expand a file	or stream

SYNOPSIS
       dact  [	-dsfcvlniCHOShVNa  ]  [-b size]	 [-e algo]  [-m	file] [-o file]	[-u url]
       [-p url]	[-M command] [-D desc] [-I algo] [-U file] [-E cipher] [file ...]

DESCRIPTION
       DACT reduces input files	by attempting to compress each	block  of  the
       file  with  several  different  algorithms and selects the best one for
       each block.

OPTIONS
       -d     Decompress the file (or stdin, if	no file	 is  given),  removing
	      the extension if it has a	valid one.

       -s     Display  statistics  about  the  file,  such as: Magic number of
	      file, DACT version file was compressed with, Block size used  to
	      compress	file, Compressed file size, Original file's size, Com-
	      pression ratio (uncompressed  to	compressed),  File's  original
	      name, CRCs (if available).

       -f     Force  bad and unsafe things to happen.  Can be combined to make
	      even worse things	happen.	 One `-f' allows overwriting of	exist-
	      ing files, two `-f' allows you to	ignore bad magic and CRC check
	      fails.

       -c     Send output to stdout, this will allow you to force DACT to send
	      compressed  output to a terminal or result of compressing	a file
	      to a pipe.

       -v     Increase verbosity, can be combined to increase verbosity	a lot.
	      Currently,  only	up  to 3 makes sense.  One `-v'	displays a bar
	      graph.  Two `-v' displays	a bar  graph  and  block  information.
	      Three `-v' displays a bar	graph and detailed compression statis-
	      tics per block.

       -l     List compression algorithms available.

       -n     Toggle use of CRCs.  This	option is especially useful when  com-
	      bined  with  the network capabilities of DACT.  It allows	you to
	      create a compressed file with only the header pointing to	a  web
	      page  that  contains  the	real DACT file (which normally has its
	      CRCs checked against the compressed header to ensure they're the
	      same  file),  with  this option the files	do not have to be from
	      the same source (i.e., you can have an  updated  copy  automati-
	      cally extend itself.)

       -i     Read  input  from	 standard  input instead of /dev/tty.  This is
	      used to read user	supplied information like encryption keys  and
	      passwords	 from  standard	 input instead of the more appropriate
	      method of	opening	"/dev/tty."

       -C     Complain when compression	errors occur.  When  a	block  is  se-
	      lected,  it is tested to ensure that it decompresses back	to the
	      original source.	If it fails, the algorithm is not  used,  with
	      this option you are informed of the failure.

       -H     Write  only  header  (no	data).	This option is useful for dis-
	      tributing	archives that need only	reside on the  internet	 some-
	      place.

       -O     Toggle  writing  original	file name in the DACT header. This has
	      no real use that I know of.

       -S     Use speed-size as	a metric rather	than size.  This is not	imple-
	      mented  yet.  This will make DACT	create an optimized compressed
	      file, balancing speed of decompression with size.

       -h     Give usage synopsis.

       -V     Display DACT version.

       -N     Upgrade DACT.  This option will fetch the	latest binary from the
	      internet	and place it in	$HOME/.dact/ as	dact.bin.  If you have
	      `binary_check on'	in your	dact.conf file,	DACT  will  check  for
	      this file	and use	it.  If	you have Debian	and run	`dact -N'   as
	      root the Debian upgrade procedure	will upgrade your entire  sys-
	      tem.

       -a     DACT  modules.   This  option will fetch the latest modules from
	      the internet and place them in $HOME/.dact/  in  a  subdirectory
	      corresponding to your Operating System and CPU Architecture.

       -b size
	      Use the specified	block size to compress the file.  The size pa-
	      rameters is in bytes.

       -e num Exclude an algorithm from	being used.  This option is useful  if
	      you  know	 your  target will not be able to decompress a certain
	      algorithm	(you can get their numbers from	the `-l' option.)

       -m file
	      Load another config file.	 This option will attempt to load  the
	      specified	 file  in addition to the normal files,	the options in
	      this file	will supersede other options.

       -o file
	      Alternate	output.	 This option sends output to a file instead of
	      INFILE.dct.  The file can	also be	a URL or '-' for standard out.

       -u url This  option will	encode an URL in the compressed	file's header,
	      this URL will be tried (and CRCs checked)	before	attempting  to
	      decompress the data in the actual	file.

       -p url URLs  in	DACT  can have variables in them that will be expanded
	      when network access is required, this allows you to test the re-
	      sults  of	that extrapolation easily.  Variables and their	values
	      are:
		  @@OSNM@@	  OS Name (linux, freebsd, sunos, etc)
		  @@OSVR@@	  OS version (2.2.x, 4.2, 5.8, etc)
		  @@OSVS@@	  OS version (short) (2.2, 4.2,	5.8, etc)
		  @@ARCH@@	  Arch (i386, sparc64, sun4u, sun4m, etc)
		  @@DIST@@	  If OSNM=Linux, distribution of Linux.
		  @@FILE@@	  Name of compressed file.
		  @@DTVR@@	  Version of DACT (maj.min.rev)
		  @@DTVS@@	  Version of DACT (short) (maj.min)
		  @@PASS@@	  Prompt for Password
		  @@USER@@	  Prompt for Username
		  @@ATSN@@	  Put an `@'
		example:
		  dact	     -p	      http://www.rkeene.org/devel/dact/precom-
	      piled/dact-@@OSNM@@-@@OSVS@@-@@ARCH@@.bin
		  dact:	    http://www.rkeene.org/devel/dact/precompiled/dact-
	      linux-2.4-i586.bin

       -M command
	      This option executes a command from the command line  as	if  it
	      appeared in "dact.conf".

       -D desc
	      Encode  the  description	specified  into	the header of the com-
	      pressed file.

       -I num Use only 1 algorithm (and	uncompressed as	a  fall-back),	useful
	      if you want to limit yourself to a certain type of compression.

       -U file
	      Encode  the  specified  file  into  the header of	the compressed
	      file.  This file will be searched	(line-by-line) for  a  working
	      URL to download compressed content from.	See also `-u.'

       -E cipher
	      Enable encryption	using the specified algorithm, different algo-
	      rithms use different authentication methods.

FILES
	 $HOME/.dact/
	 $HOME/.dact/dact.conf
	 /usr/etc/dact.conf

SEE ALSO
       gzip(1),	bzip2(1), mcrypt(3)

AUTHOR
       Roy Keene _dact@rkeene.org_

								       DACT(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILES | SEE ALSO | AUTHOR

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