This version will work if "*screenflow" returns any results with weird characters, and will actually compress the tarballs.

Use find's built-in "exec" option to avoid having to do any weirdness with quoting.

don't bother spawning a bc process or counting the number of options, just pick a random one. 'sort -R' sorts randomly, so pick the top one.

The "find $stuff -print0 | xargs -0 $command" pattern causes both find and xargs to use null-delineated paths, greatly reducing the probability of either hiccuping on even the weirdest of file/path names. It's also not strictly necessary to add the {} at the end of the xargs command line, as it'll put the files there automatically. Mind, in most environments, you could use find's "-exec" option to bypass xargs entirely: find . -name '*.jpg' -o -name '*.JPG' -exec mogrify -resize 1024">" -quality 40 {} + will use xargs-like "make sure the command line isn't too long" logic to run the mogrify command as few times as necessary (to run once per file, use a ';' instead of a '+' - just be sure to escape it properly).

This will generate the same output without changing the current directory, and filepath will be relative to the current directory. Note: it will (still) fail if your iTunes library is in a non-standard location.

With the plus instead of semicolon, find builds the (eg.) rm command like xargs does - invokes as few extra processes as possible.

The "-k" flag will tell wget to convert links for local browsing; it works with mirroring (ie with "-r") or single-file downloads.

Use find's built-in ability to call programs. Alternatively, find -maxdepth 1 -type f -name "*.7z" -print0 | xargx -0 -n 1 7zr e would work, too.