At the end of the script, the URL generated from the newly created ix.io pastebin is put into the X buffer (so that it can be pasted into other X applications). This is done via the
xclip command, but
xclip is not installed everywhere, so the
ix script checks that it is available before trying to use it:
which xclip >/dev/null || exit 0
echo "$url" | xclip
This is a common pattern.
Because the use of
xclip here is right at the end of the script (by design, most likely) it's possible to abort (
|| exit 0) if
xclip isn't there. I guess an alternative, if it was necessary to run it mid-script, would be something like this:
which xclip >/dev/null && echo "$url" | xclip
Anyway, worth knowing and having seen it, right?