What type of projects are you trying to build? Are you working on embedded technology or are you building web apps? The type of environment you work in will help decide. C is still a relevant and powerful language, but there are more modern alternatives in the same space like Rust.

Maybe if you want to write a kernel driver or a file system.

You can't go wrong with it. But for what purpose?

If you want to work, for example, in embedded systems it's a must

imho: always

especially if you are in to hardware, embedded, hpc, ... usecases.

For network programming, you might consider asynchronous programming with coroutines. C++20 has them and they're already supported in LLVM. For C, there are a number of implementations of coroutines: https://en.wikipedia.org/wiki/Coroutine#Implementations_for_...

Once a second call stack has been obtained with one of the methods listed above, the setjmp and longjmp functions in the standard C library can then be used to implement the switches between coroutines. These functions save and restore, respectively, the stack pointer, program counter, callee-saved registers, and any other internal state as required by the ABI, such that returning to a coroutine after having yielded restores all the state that would be restored upon returning from a function call. Minimalist implementations, which do not piggyback off the setjmp and longjmp functions, may achieve the same result via a small block of inline assembly which swaps merely the stack pointer and program counter, and clobbers all other registers. This can be significantly faster, as setjmp and longjmp must conservatively store all registers which may be in use according to the ABI, whereas the clobber method allows the compiler to store (by spilling to the stack) only what it knows is actually in use.

CPython's asyncio implementation (originally codenamed 'tulip') is written in C and IMHO much easier to use than callbacks like Twisted and JS before Promises and the inclusion of tulip-like async/await keywords in ECMAscript. Uvloop - based on libuv, like Node - is apparently the fastest asyncio event loop. CPython Asyncio C module source: https://github.com/python/cpython/blob/master/Modules/_async... Asyncio docs: https://docs.python.org/3/library/asyncio.html

(When things like file or network I/O are I/O bound, the program can yield to allow other asynchronous coroutines ('async') to run on that core. With network programming, we're typically waiting for things to send or reply.)

Return-oriented-programming > Return-into-library technique is an interesting read regarding system programming :) https://en.wikipedia.org/wiki/Return-oriented_programming#Re...

Only matters if you want to work in embedded devices/IoT, operating systems, any other type of systems development or high-performance development, and some segments of game development or games middleware.

Yes. Many current hot languages are based on the C's structure plus there are millions of lines of C code that need maintenance. It's worth learning now and it will be worth learning 10 years from now.

I say yes because, as others have pointed out, C is at the base of nearly everything. If not C then you should learn some systems level language, be it C, D, rust or whatever. If you want to know how modern computing actually works then that's the way to do it.

You'll learn lessons that will teach you how to avoid common pitfall mistakes in higher level languages. And you'll be able to interop with C/C++ libraries which can be quite useful. And your code will run faster than most other languages can achieve. There are lots of reasons to learn C even today.

Most certainly. I do suggest C++ over C though, for a higher paying job.

yes