Actually yeah, those are.

This is a good list.

There are three kinds of Linux commands:

• commands I use frequently
• commands I’ve never seen or don’t know about. There’s almost nothing in standard POSIX that falls in this category, and a lot of OSS that does. E.g., I use to always reach for fuser until I realized it’s not a base install on many distros, so I switched to lsof which is is, and is also both more powerful and harder to use.
• commands I’ve seen before but use so infrequently I forget they exist, or what they’re called. This is sadly a larger set than I’d like.

Some of these in this list are the third kind.

Most people will run a post 2.6 kernel, so prlimit will be available as an interesting alternative to ulimit.

Nice.

Looks like the site is down or blocked in my country.

Could anyone please be so nice and copy paste those commands here?

The most interesting command for the Linux shell is known as Barmin patch.