(05-06-2021, 03:25 AM)venam Wrote: The "sub tools category", the programs that start with a name such
as openssl and then followed by a sub command. The sub command itself
takes flags.
I can thing of git, openssl, imagemagic fork called graphicsmagick "gm",
busybox? and others..

There's also the "split programs framework" approach: When a "software"
installs a bunch of other sub-software/tools as framework.
Either all these software in the "framework" start with the same
prepended form, fc- for font config for example. Or they come
under a single tool to avoid confusion.
Sometimes it's annoying if a software installs subtools in that
"framework" but they all have very different name, it makes it hard
to find related functionalities, discoverability is very low.
Again, I'd say this is an observation in tune with the book: ease of
use for human-brains.

plan9 does subtools in a very elegant way: as binaries in sub-directories in your $path (which, in plan9, is merged into /bin/).
Rather than a master command git(1) have subcomands clone, log, etc; they are all grouped in a subdirectory at /bin (/bin/git). The system will look on subdirectories at /bin/ and call the binary accordingly. Here's an example from 9front port of git: