Beej himself lists this as an 'alpha-quality document' on the download page [0] and if I remember correctly, it has been so for years. Wonder why this is posted here on HN.
And I'm sure it's full of mistakes. It's over 500 pages, most of which has yet to be edited, so if there are fewer than 1000 defects, I'd be shocked.
But I fix them all as I find them, or as they're pointed out. And after an eventual editing pass, things will be better.
And if it's not useful to someone, I take no offense I'd they don't like it. :-)
But I became disinterested because:
1. Most beginning programmers don't start with C
2. I wouldn't get a chance to go deep and explore the language.
So I shelved it, unfinished.
Flash forward to about a year ago... I had flash of inspiration: change the audience to intermediate programmers.
Now I could skim the general conceptual stuff and get into more details.
One thing, though. C actually added a lot of stuff in the intervening years. I didn't realize the magnitude of the project.
Oh well! Too late to turn back now!
Except literally every indian engineer. They teach C to mechanical and chemical engineers for some reason. (It's not an elective)