NAME

       zupdate - recompress bzip2, gzip, xz, zstd files to lzip format

SYNOPSIS

       zupdate [options] [files]

DESCRIPTION

       zupdate  recompresses  files  from  bzip2, gzip, xz, and zstd formats to lzip format. Each
       original is compared with the new file and then deleted.  Only regular files with standard
       file  name  extensions  are  recompressed,  other  files are ignored. Compressed files are
       decompressed and then recompressed on the fly; no temporary files are  created.  The  lzip
       format  is  chosen  as  destination  because it is the most appropriate for long-term data
       archiving.

       If no files are specified, recursive searches examine the current working  directory,  and
       nonrecursive searches do nothing.

       If  the  lzip  compressed version of a file already exists, the file is skipped unless the
       option '--force' is given. In this case, if the comparison with the existing lzip  version
       fails, an error is returned and the original file is not deleted. The operation of zupdate
       is meant to be safe and not cause any data loss. Therefore, existing lzip compressed files
       are never overwritten nor deleted.

       The names of the original files must have one of the following extensions:

       '.bz2', '.gz', '.xz', or '.zst', which are recompressed to '.lz'.

       '.tbz', '.tbz2', '.tgz', '.txz', or '.tzst', which are recompressed to '.tlz'.

       Exit  status  is 0 if all the compressed files were successfully recompressed (if needed),
       compared, and deleted (if requested). Non-zero otherwise.

OPTIONS

       -h, --help
              display this help and exit

       -V, --version
              output version information and exit

       -f, --force
              don't skip a file even if the .lz exists

       -k, --keep
              keep (don't delete) input files

       -l, --lzip-verbose
              pass one option -v to the lzip compressor

       -M, --format=<list>
              process only the formats in <list>

       -N, --no-rcfile
              don't read runtime configuration file

       -q, --quiet
              suppress all messages

       -r, --recursive
              operate recursively on directories

       -R, --dereference-recursive
              recursively follow symbolic links

       -v, --verbose
              be verbose (a 2nd -v gives more)

       -0 .. -9
              set compression level [default 9]

       --bz2=<command>
              set compressor and options for bzip2 format

       --gz=<command>
              set compressor and options for gzip format

       --lz=<command>
              set compressor and options for lzip format

       --xz=<command>
              set compressor and options for xz format

       --zst=<command>
              set compressor and options for zstd format

REPORTING BUGS

       Report bugs to zutils-bug@nongnu.org
       Zutils home page: http://www.nongnu.org/zutils/zutils.html

COPYRIGHT

       Copyright © 2022  Antonio  Diaz  Diaz.   License  GPLv2+:  GNU  GPL  version  2  or  later
       <http://gnu.org/licenses/gpl.html>
       This  is free software: you are free to change and redistribute it.  There is NO WARRANTY,
       to the extent permitted by law.

SEE ALSO

       The full documentation for zupdate is maintained as a Texinfo manual.   If  the  info  and
       zupdate programs are properly installed at your site, the command

              info zutils

       should give you access to the complete manual.