Bash is so powerful it scares me. It’s like Fred Flintstone riding a dinosaur to work: one false move and it’s gonna be mad destruction. So I love me some man pages. I also dig through the better online references.
If you want man pages for a specific version of Ubuntu, nothing beats manpages.ubuntu.com. Check out results for a search on xargs.
For a thorough generic explanation (often drawn from the above site) I like Explainshell.com. It documents exactly how commands and all their options work. Okay, “all” may be optimistic, given OS variations, but each page specifies what version(s) it applies to. Follow the link below to see what a simple search returns. Click xargs on the page to go to the full man page.
Know of any more great resources like this? Drop me a line using the Contact link above. Happy Bashing.