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', '.zst', or '.Z', 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). 1 if a non-fatal error occurred (file not found or not regular, or has invalid format, or can't be deleted). 2 if a fatal error occurred (compressor can't be run, or comparison fails).

OPTIONS¶

-h, --help

display this help and exit

-V, --version

output version information and exit

-e, --expand-extensions

expand combined extensions; tgz -> tar.lz

-f, --force

don't skip a file even if the .lz exists

-i, --ignore-errors

ignore non-fatal errors

-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.