lzop - compress or expand files


   lzop is a file compressor very similar to gzip.  lzop favors speed over
   compression ratio.


   lzop [ command ] [ options ] [ filename ...  ]

   lzop [-dxlthIVL19] [-qvcfFnNPkU] [-o file] [-p[path]] [-S suffix]
   [filename ...]


   lzop reduces the size of the named files. Whenever possible, each file
   is compressed into one with the extension .lzo, while keeping the same
   ownership modes, access and modification times. If no files are
   specified, or if a file name is "-", lzop tries to compress the
   standard input to the standard output. lzop will only attempt to
   compress regular files or symbolic links to regular files.  In
   particular, it will ignore directories.

   If the compressed file name is too long for its file system, lzop
   truncates it.

   Compressed files can be restored to their original form using lzop -d.
   lzop -d takes a list of files on its command line and decompresses each
   file whose name ends with .lzo and which begins with the correct magic
   number to an uncompressed file without the original extension. lzop -d
   also recognizes the special extension .tzo as shorthand for .tar.lzo.
   When compressing, lzop uses the .tzo extension if necessary instead of
   truncating a file with a .tar extension.

   lzop stores the original file name, mode and time stamp in the
   compressed file. These can be used when decompressing the file with the
   -d option. This is useful when the compressed file name was truncated
   or when the time stamp was not preserved after a file transfer.

   lzop preserves the ownership, mode and time stamp of files when
   compressing. When decompressing lzop restores the mode and time stamp
   if present in the compressed files.  See the options -n, -N, --no-mode
   and --no-time for more information.

   lzop always keeps original files unchanged unless you use the option

   lzop uses the LZO data compression library for compression services.
   The amount of compression obtained depends on the size of the input and
   the distribution of common substrings.  Typically, text such as source
   code or English is compressed into 40-50% of the original size, and
   large files usually compress much better than small ones. Compression
   and decompression speed is generally much faster than that achieved by
   gzip, but compression ratio is worse.

   lzop offers the following compression levels of the LZO1X algorithm:

   -3  the default level offers pretty fast compression.  -2, -3, -4, -5
       and -6 are currently all equivalent - this may change in a future

   -1, --fast
       can be even a little bit faster in some cases - but most times you
       won't notice the difference

   -7, -8, -9, --best
       these compression levels are mainly intended for generating pre-
       compressed data - especially -9 can be somewhat slow

   Decompression is very fast for all compression levels, and
   decompression speed is not affected by the compression level.


   If no other command is given then lzop defaults to compression (using
   compression level -3).

   -#, --fast, --best
       Regulate the speed of compression using the specified digit #,
       where -1 or --fast indicates the fastest compression method (less
       compression) and -9 or --best indicates the slowest compression
       method (best compression). The default compression level is -3.

   -d, --decompress, --uncompress
       Decompress. Each file will be placed into same the directory as the
       compressed file.

   -x, --extract
       Extract compressed files to the current working directory. This is
       the same as '-dPp'.

   -t, --test
       Test. Check the compressed file integrity.

   -l, --list
       For each compressed file, list the following fields:

         method: compression method
         compressed: size of the compressed file
         uncompr.: size of the uncompressed file
         ratio: compression ratio
         uncompressed_name: name of the uncompressed file

       In combination with the --verbose option, the following fields are
       also displayed:

         date & time: time stamp for the uncompressed file

       With --name, the uncompressed name, date and time are those stored
       within the compress file if present.

       With --verbose, the size totals and compression ratio for all files
       is also displayed. With --quiet, the title and totals lines are not

       Note that lzop defines compression ratio as compressed_size /

   --ls, --ls=FLAGS
       List each compressed file in a format similar to ls -ln.

       The following flags are currently honoured:
         F  Append a '*' for executable files.
         G  Inhibit display of group information.
         Q  Enclose file names in double quotes.

       For each compressed file, list the internal header fields.

   -I, --sysinfo
       Display information about the system and quit.

   -L, --license
       Display the lzop license and quit.

   -h, -H, --help
       Display a help screen and quit.

   -V  Version. Display the version number and compilation options and

       Version. Display the version number and quit.


   -c, --stdout, --to-stdout
       Write output on standard output. If there are several input files,
       the output consists of a sequence of independently (de)compressed
       members. To obtain better compression, concatenate all input files
       before compressing them.

   -o FILE, --output=FILE
       Write output to the file FILE. If there are several input files,
       the output consists of a sequence of independently (de)compressed

   -p, -pDIR, --path=DIR
       Write output files into the directory DIR instead of the directory
       determined by the input file. If DIR is omitted, then write to the
       current working directory.

   -f, --force
       Force lzop to

        - overwrite existing files
        - (de-)compress from stdin even if it seems a terminal
        - (de-)compress to stdout even if it seems a terminal
        - allow option -c in combination with -U

       Using -f two or more times forces things like

        - compress files that already have a .lzo suffix
        - try to decompress files that do not have a valid suffix
        - try to handle compressed files with unknown header flags

       Use with care.

   -F, --no-checksum
       Do not store or verify a checksum of the uncompressed file when
       compressing or decompressing.  This speeds up the operation of lzop
       a little bit (especially when decompressing), but as unnoticed data
       corruption can happen in case of damaged compressed files the usage
       of this option is not generally recommended.  Also, a checksum is
       always stored when compressing with one of the slow compression
       levels (-7, -8 or -9), regardless of this option.

   -n, --no-name
       When decompressing, do not restore the original file name if
       present (remove only the lzop suffix from the compressed file
       name). This option is the default under UNIX.

   -N, --name
       When decompressing, restore the original file name if present. This
       option is useful on systems which have a limit on file name length.
       If the original name saved in the compressed file is not suitable
       for its file system, a new name is constructed from the original
       one to make it legal.  This option is the default under DOS,
       Windows and OS/2.

   -P  When decompressing, restore the original path and file name if
       present.  When compressing, store the relative (and cleaned) path
       name.  This option is mainly useful when using archive mode - see
       usage examples below.

       When decompressing, do not restore the original mode (permissions)
       saved in the compressed file.

       When decompressing, do not restore the original time stamp saved in
       the compressed file.

   -S .suf, --suffix=.suf
       Use suffix .suf instead of .lzo. The suffix must not contain
       multiple dots and special characters like '+' or '*', and suffixes
       other than .lzo should be avoided to avoid confusion when files are
       transferred to other systems.

   -k, --keep
       Do not delete input files. This is the default.

   -U, --unlink, --delete
       Delete input files after succesfull compression or decompression.
       Use this option to make lzop behave like gzip and bzip2.  Note that
       explicitly giving -k overrides -U.

       Use a crc32 checksum instead of a adler32 checksum.

       Suppress all warnings.

       Suppress all warnings, and never exit with exit status 2.

   -q, --quiet, --silent
       Suppress all warnings and decrease the verbosity of some commands
       like --list or --test.

   -v, --verbose
       Verbose. Display the name for each file compressed or decompressed.
       Multiple -v can be used to increase the verbosity of some commands
       like --list or --test.

   --  Specifies that this is the end of the options. Any file name after
       -- will not be interpreted as an option even if it starts with a


       Do not try to read standard input (but a file name "-" will still
       override this option).  In old versions of lzop, this option was
       necessary when used in cron jobs (which do not have a controlling

       Rarely useful.  Preprocess data with a special "multimedia" filter
       before compressing in order to improve compression ratio.  NUMBER
       must be a decimal number from 1 to 16, inclusive.  Using a filter
       slows down both compression and decompression quite a bit, and the
       compression ratio usually doesn't improve much either...  More
       effective filters may be added in the future, though.

       You can try --filter=1 with data like 8-bit sound samples,
       --filter=2 with 16-bit samples or depth-16 images, etc.

       Un-filtering during decompression is handled automatically.

   -C, --checksum
       Deprecated. Only for compatibility with very old versions as lzop
       now uses a checksum by default. This option will get removed in a
       future release.

       Do not use any color escape sequences.

       Assume a mono ANSI terminal. This is the default under UNIX (if
       console support is compiled in).

       Assume a color ANSI terminal or try full-screen access. This is the
       default under DOS and in a Linux virtual console (if console
       support is compiled in).


   lzop allows you to deal with your files in many flexible ways. Here are
   some usage examples:

   backup mode
      tar --use-compress-program=lzop -cf archive.tar.lzo files..

      This is the recommended mode for creating backups.
      Requires GNU tar or a compatible version which accepts the
      '--use-compress-program=XXX' option.

   single file mode: individually (de)compress each file
       lzop a.c             -> create a.c.lzo
       lzop a.c b.c         -> create a.c.lzo & b.c.lzo
       lzop -U a.c b.c      -> create a.c.lzo & b.c.lzo and delete a.c & b.c
       lzop *.c

       lzop -d a.c.lzo      -> restore a.c
       lzop -df a.c.lzo     -> restore a.c, overwrite if already exists
       lzop -d *.lzo

       lzop -l a.c.lzo
       lzop -l *.lzo
       lzop -lv *.lzo       -> be verbose

       lzop -t a.c.lzo
       lzop -tq *.lzo       -> be quiet

   pipe mode: (de)compress from stdin to stdout
       lzop < a.c > y.lzo
       cat a.c | lzop > y.lzo
       tar -cf - *.c | lzop > y.tar.lzo     -> create a compressed tar file

       lzop -d < y.lzo > a.c
       lzop -d < y.tar.lzo | tar -xvf -     -> extract a tar file

       lzop -l < y.lzo
       cat y.lzo | lzop -l
       lzop -d < y.tar.lzo | tar -tvf -     -> list a tar file

       lzop -t < y.lzo
       cat y.lzo | lzop -t

   stdout mode: (de)compress to stdout
       lzop -c a.c > y.lzo

       lzop -dc y.lzo > a.c
       lzop -dc y.tar.lzo | tar -xvf -      -> extract a tar file

       lzop -dc y.tar.lzo | tar -tvf -      -> list a tar file

   archive mode: compress/extract multiple files into a single archive
       lzop a.c b.c -o sources.lzo          -> create an archive
       lzop -P src/*.c -o sources.lzo       -> create an archive, store path name
       lzop -c *.c > sources.lzo            -> another way to create an archive
       lzop -c *.h >> sources.lzo           -> add files to archive

       lzop -dN sources.lzo
       lzop -x ../src/sources.lzo           -> extract to current directory
       lzop -x -p/tmp < ../src/sources.lzo  -> extract to /tmp directory

       lzop -lNv sources.lzo

       lzop -t sources.lzo
       lzop -tvv sources.lzo                -> be very verbose

   If you wish to create a single archive file with multiple members so
   that members can later be extracted independently, you should prefer a
   full-featured archiver such as tar. The latest version of GNU tar
   supports the --use-compress-program=lzop option to invoke lzop
   transparently.  lzop is designed as a complement to tar, not as a


   The environment variable LZOP can hold a set of default options for
   lzop. These options are interpreted first and can be overwritten by
   explicit command line parameters.  For example:

       for sh/ksh/zsh:    LZOP="-1v --name"; export LZOP
       for csh/tcsh:      setenv LZOP "-1v --name"
       for DOS/Windows:   set LZOP=-1v --name

   On Vax/VMS, the name of the environment variable is LZOP_OPT, to avoid
   a conflict with the symbol set for invocation of the program.

   Not all of the options are valid in the environment variable - lzop
   will tell you.


   bzip2(1), gzip(1), tar(1)

   Precompiled binaries for some platforms are available from the lzop
   home page.

       see http://www.oberhumer.com/opensource/lzop/

   lzop uses the LZO data compression library for compression services.

       see http://www.oberhumer.com/opensource/lzo/


   Exit status is normally 0; if an error occurs, exit status is 1. If a
   warning occurs, exit status is 2 (unless option --ignore-warn is in

   lzop's diagnostics are intended to be self-explanatory.


   No bugs are known. Please report all problems immediately to the


   Markus Franz Xaver Johannes Oberhumer <markus@oberhumer.com>


   lzop and the LZO library are Copyright (C) 1996, 1997, 1998, 1999,
   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 by
   Markus Franz Xaver Johannes Oberhumer.  All Rights Reserved.

   lzop and the LZO library are distributed under the terms of the GNU
   General Public License (GPL).

   Legal info: If want to integrate lzop into your commercial
   (backup-)system please carefully read the GNU GPL FAQ at
   http://www.gnu.org/licenses/gpl-faq.html about possible implications.


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