NAME

       zst - compress or decompress .zst/.bz2/.gz/.xz files

SYNOPSIS

       zst [options] files...

DESCRIPTION

       The  zst  command  can  reduce  the size of files by using a number of popular compression
       algorithms; in this version these are zstd, bzip2, xz, gzip -- and decompress them back.

       While these compressors' native tools may expose more options specific to the algorithm in
       question,  zst unifies them with common functionality.  Eg, only gzip and zstd can recurse
       with -r, zstd defaults to -k and its levels go up to 19 rather than 9, etc.

       The default compressor is zstd as it's fastest while also compressing well; you  may  want
       to  use  xz instead when disk space / network bandwidth is at premium.  On the other hand,
       neither gzip nor bzip2 are a superior choice in any case but especially gzip is entrenched
       for historical reasons.

OPTIONS

       Mode of operation

       -z     Compress  (default).   The  file  will  be  replaced  by  a compressed copy with an
              appropriate suffix added: .zst/.bz2/.xz/.gz according to the algorithm used.

       -d     Decompress.  Files without a known suffix will be left untouched.

       -t     Test the integrity of compressed files; this is functionally same as  decompression
              redirected to /dev/null.

       Modifiers

       -c     Write  compressed  or  decompressed data to standard output.  This implies -k.  For
              compression, if the stdout is a terminal, -f must be also specified.

       -k     The source file won't be removed after [de]compression.

       -f     Will overwrite existing files.  Allows writing compressed data to a terminal.  When
              -c  is  given and the data is not in the expected format, it will be passed through
              unmodified.  Allows compressing a file that's already compressed.

       -r     If a directory is among file names specified on the command line, all files  inside
              will be processed, possibly recursing into directories deeper in.

       -1..-9 Compression  level:  -1 is the weakest but fastest level the algorithm knows, -9 is
              strongest and slowest.  Note that unlike the zstd tool, the scale is 1..9  for  all
              algorithms -- level 9 corresponds to what zstd knows as 19.

              The defaults are: zst 2, bz2 9, gz 6, xz 6.

       -v     List  all  processed  files.   When  compressing,  the  old, new, and percentage of
              required size is given.

       -q     Suppress all warnings.  Unrelated to -v.

       -n     Ignored; for compat with gzip.

       -F     Specify compression algorithm to use.

RETURN VALUE

       1 if any errors happened, 2 if there's a warning but no errors, 0 if all went ok.

SEE ALSO

       zstd(1), bzip2(1), gzip(1), xz(1).

                                            2022-10-18                                     zst(1)