Early in my career these books were the most helpful to me as a self taught developer:

* CSS Pocket Reference - Eric Meyer - https://www.amazon.com/CSS-Pocket-Reference-Visual-Presentat...

* XML Schema - Priscilla Walmsley - https://www.amazon.com/Definitive-XML-Schema-Priscilla-Walms...

* DOM Scripting - Jeremy Keith - https://www.amazon.com/DOM-Scripting-Design-JavaScript-Docum...

Some of my favorites that have stayed at least pretty relevant. Disclosure: not an old timer.

- UNIX and Linux System Administration Handbook. Get the most recently volume. It's a tomb (~1200 for the most recent).

- If you do any SQL, SQY Performance Explained is an 80/20 read for DB indexes, query optimization, and troubleshooting

- A Philosophy of Software Design (more recent). Just a great book on good design considerations to keep in mind.

- Mastering Regular Expressions. The first half of the book will make you confident. The second half will show you how they're implemented. Regular expressions aren't something to be afraid of!

- Designing Data Intensive Applications (more recent). Great book about data infra design decisions. Maybe not the scope you're looking for though.

- Design Patterns (Gang of Four). Absolute classic. Hard to read all the way through though, more of a reference read. You'll recognize a lot of the patterns. You'll find some great to see a formal definition of, and you'll see some you never want to use.

- Clean Architecture - Uncle Bob's best book IMO. I really don't like Clean Code, but this book talks a lot about interfaces and the right level of separation in your systems.

- K&R, as you mentioned, is of course a classic

- The AWK Programming Language is a nice quick read with similar quality and structure to K&R.

- Beej's Guide to Network Programming. The best overview of network programming, including the C API. Plus this book is genuinely funny. Beej has a ton of great stuff, all on their website for free, or in print.

- The Rust Programming Language is very well written too. Also online for free or in print.

As an old-timer, I worry that it may have been forgotten that all the major systems vendors used to have extensive shelves of high-quality technical manuals for their software, written by their in-house teams of professional technical writers. And many of them were really good, especially the ones on programming languages. The Univac APL 1100 manual might be the best book on APL ever, for example, and the CDC Fortran manual was a superb reference. I wonder if any of these old gems are available on-line.

Been doing this software thing for 35 years so I guess that makes me an old timer.

Technical books, especially for practitioners, that stay relevant over a long period of time are rather rare. I wish I could say that I've had time to study TAoCP or SICP, but I haven't.

Some of what I did find useful back in the day were: Advanced Programming in the Unix Environment by Stevens, Stan Lippman's C++ book, Code Complete by Steve McConnell, the GoF Design Patterns book, Working Effectively With Legacy Code by Michael Feathers, and Introduction to Artificial Intelligence by Charniak and McDermott.

Whether, and to what extent, any of them are useful now is hard to say. Depends what you want to learn and what you're doing. The Charniak book, for example, is about classic "good old fashioned" AI, not the currently dominant connectionist approach. But it's LISP, and LISP is always relevant.

I'd also add The Systems Bible by John Gall as a book that influenced me. Its not a technology book though.

I'm not an old timers, but I have the following books in my library:

- The Design of the Unix Operating System

- The elements of programming style

- Code Complete, 2nd Edition

- The Art of Unix Programming

- Advanced Programming in the Unix Environment

- TCP/IP Illustrated, Volume 1

Surprised no mention yet of The Design and Implementation of the 4.4BSD Operating System

I’m not an old timer and I do read tech books on a weekly basis. It’s the only way for me to stay sharp in the industry. I also read documentation ofc. As for which books, the good ones.

I’ve never done an online course or a bootcamp.

The Turbo Pascal manual was one of the best ever.

If you had access to a DEC based minicomputer, their wall of manuals was a perfect technical reference for their systems.

Knuth's series, the art of computer programming is a classic.

In 1968 all we had was McCracken's short book on FORTRAN and a large number of utterly inpenetrable IBM manuals. When IBM finally came out with "FORTRAN Programmers Guide", it was revolutionary. Asking other programmers was very useful.

None of this is useful for you other than discussing things with fellow programmers.

https://linux.die.net/man/

For a classic CS view around the year 2000:

* Concepts, Techniques, and Models of Computer Programming

* Engineering a Compiler

* The Elements of Computing Systems

A lot of the GNU manuals + Linux HOWTOs are pretty good for bash, make, coreutils, etc etc.

Don Knuths AoCP

SICP, Abelson and Sussman

Stroustrup

Aho and Ullman compilers

A Commentary on the UNIX Operating System

GNU C Library

Michael Kerrisks books are newer but are exceptional

K&R, Stevens, Borne’s shell book. Other books from the bell lab people.

Jon Bentley's original 2-volume "Programming Pearls". I haven't looked at the 2nd, single volume, edition.

Pike and Kernighan's "The Unix Programming Environment", and their later book "The Practice of Programming"

Usenix put out a refereed journal "Computing Systems" that was really good: https://www.usenix.org/publications/compsystems/computing-sy...

The C++ Programming Language by Stroutrup

Programming Perl (the camel book)

Unix I just kind of learned by using it.