> For a while, new options were getting added to GNU tar frequently in order > to allow you to do things like > > compress -dc | tar xf - > zcat | tar xf - > bzcat | tar xf - > lzcat | tar xf - > > etc., but just using the single tar invocation without (explicitly > running) an external compression program. The current ones are (in > alphabetical order in the man page, not historical order of when they > were added) > > -j, --bzip2 > Filter the archive through bzip2(1). > > -J, --xz > Filter the archive through xz(1). > > --lzip Filter the archive through lzip(1). > > --lzma Filter the archive through lzma(1). > > --lzop Filter the archive through lzop(1). > > -z, --gzip, --gunzip, --ungzip > Filter the archive through gzip(1). > > -Z, --compress, --uncompress > Filter the archive through compress(1). > > --zstd Filter the archive through zstd(1). > > Wow, eight specific forms of compression! But a newer functionality > in GNU tar is > > -a, --auto-compress > Use archive suffix to determine the compression program. > > and something like that (apparently also looking at the file header) > is now the default. > > It's weird to me to imagine having all of that functionality in grep, > but maybe all of the functionality that was put into tar for this could > become a separate standalone program?
GNU tar also supports `-I, --use-compress-program=PROG filter through PROG (must accept -d)`, which is one of the reasons I thought it would be relevant to add a similar option to grep.
