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Amazing comment, thank you for your detailed input and the awesome resources. I want to get into C because I like network and system programming but lack the un

• westurner 7y ago
  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_C 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/_asynciomodule.c https://github.com/python/cpython/blob/master/Modules/_async... Asyncio docs: https://docs.python.org/3/library/asyncio.html 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#Return-into-library_technique https://en.wikipedia.org/wiki/Return-oriented_programming#Re...