Documentation: Man 1 3 and 9

I was wondering if there is a standard for when Man 1, Man 3 and Man 9 folders are used for saving documentation?

I think I have it figured out, but I think I found an anomaly and before I change something (being a noob) I thought I'd ask as the only daft question is one that is not asked.

Man 1 = userspace components
github.com/robertspark/linuxcnc/tree/master/docs/man/man1

Man 3 = API calls
github.com/robertspark/linuxcnc/tree/master/docs/man/man3

Man 9 = realtime components
github.com/robertspark/linuxcnc/tree/master/docs/man/man9

anomaly (sure there may be others):
hal_parport is a realtime component (acording to the man file) + a driver?? and is listed in Man 1 (under userspace components).
github.com/robertspark/linuxcnc/blob/mas...n/man1/hal_parport.1

should it be deleted from MAN1 and added to MAN3?
{will this create a problem if I raised pull requests as such}

here to hopefully help, not hinder and treat on toes or break anything.

Note: sorry just noticed that the links are to my fork of linuxcnc git, same applies with the master, can't be bothered to change the links, I'm sure you get the idea). I've only changed 1 file in my fork (components.txt)

The history of these section numbers goes back to the original Unix Programmer's Manual by Thompson and Ritchie in 1971.

The original sections were

1 Commands
2 System calls
3 Subroutines
4 Special files
5 File formats
6 User-maintained programs
7 Miscellaneous

So I ASSUME that the creators of the Enhanced Machine Control at project at NIST followed the Unix protocol for man (manual) pages.

IMHO it's not important where the man page is except for the html documents which group the man pages into categories.

JT