I read through it and found it interesting for the historical info and as a way to review the standard library. But if you're trying to get better at C, there

I read through it and found it interesting for the historical info and as a way to review the standard library. But if you're trying to get better at C, there are probably a lot of resources that are better uses of your time. It's pretty dated, the structure is a little hard to follow (he goes in alphabetical order of the header names, which given that a lot of the libraries reference each other, makes for somewhat confusing reading), and since he isn't targeting any particular architecture, the OS dependent stuff is pretty handwavy.