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 (invalid command line options, compressor can't be run, or comparison fails).

OPTIONS

-h, --help: display this help and exit
-V, --version: output version information and exit
-d, --destdir=<dir>: write recompressed files into <dir>
-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

Valid formats for option '-M' are 'bz2', 'gz', 'lz', 'xz', and 'zst'.

REPORTING BUGS

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

COPYRIGHT