Please, tell me where to get information on the GNU Linux libraries?

[alekseypython]

Kubuntu 20.10

I'm interested in the already implemented HIGH-LEVEL functionality, which is presented in the system in the form of libraries. For example, I want to use encryption, archiving or video viewing in my application. I don't want to implement all this from 0, but I want to take existing GNU libraries, in which all this has been written for a long time ago, and just call their methods. Those, I don't want to reinvent the wheel and try to speed up my development by reusing existing code.

If you take books by programming for Linux, then everyone will have approximately the same LOW-LEVEL content: thread creation, network connections, I / O operations, interprocessor communication ... All this doesn't interest me.

Are there any books on the already realized potential of the GNU Linux world?

[TheFu]

Not sure I understand, but there is a book that explains how and why Linus created Linux. "Just for Fun" - it is a quick read. It explains what he started out to accomplish - a terminal emulator and how that grew into a POSIX OS.

Otherwise, you'll want to find an OS design book like they use in University.