Is there any nice signal I can send to the kicad software so that it will quit and save? I’m having the issue that I just opened up cvpcb and it seems to have frozen the UI while fetching things online. It stayed frozen for ~10 minutes. I would like to send a signal to tell it to just quit and save whatever I’ve been working on.
Will any of the traditional signals like SIGHUP, SIGINT, SIGQUIT, SIGUSR1 exit gracefully?
The better option would be to setup local footprint libs.
This way kicad does not need to wait for any online resource. (After the initial download is done.)
Killing kicad does not solve your underlying problem. At some point kicad needs to get the footprint information. If it takes 10 minutes for you, your internet is clearly too slow to use online libs. (online libs have other problems but for you the main problem will always be your slow internet.)
Have a look at the tutorial of @bobc to setup local libs.