According to the source, -R should be setting RLIMIT_RTTIME, but it does not work:
bash-5.0$ ulimit -R bash: ulimit: -R: invalid option ulimit: usage: ulimit [-SHabcdefiklmnpqrstuvxPT] [limit] ..and looking at the above help, I notice letters I never saw. Lets try them? bash-5.0$ ulimit -b bash: ulimit: -b: invalid option ulimit: usage: ulimit [-SHabcdefiklmnpqrstuvxPT] [limit] bash-5.0$ ulimit -k bash: ulimit: -k: invalid option ulimit: usage: ulimit [-SHabcdefiklmnpqrstuvxPT] [limit] bash-5.0$ ulimit -P bash: ulimit: -P: invalid option ulimit: usage: ulimit [-SHabcdefiklmnpqrstuvxPT] [limit] bash-5.0$ ulimit -T bash: ulimit: -T: invalid option ulimit: usage: ulimit [-SHabcdefiklmnpqrstuvxPT] [limit] They probably should not be in help if they don't work.
