From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.9) Gecko/20020311 Description of problem: The key combination ctrl-4 crashes less. ctrl-<any other number> doesn't. Version-Release number of selected component (if applicable): less-358-21 How reproducible: Always Steps to Reproduce: 1. less foo 2. type ctrl-4 Actual Results: Core dumps Expected Results: Not core dump.
That's a standard Linux behaviour on SIGQUIT (see signal(7)), which is sent to the program on <Ctrl+\> (type "stty -a", and you'll see that "quit = ^\"). And <Ctrl+4> is the same as <Ctrl+\>.