How to find out what functions are available in a dll?

Question

C++ / C#

Do not kick if the question is not very correct, but actually, how to find out which functions can be used from a dll? For example, I have a certain program, it has a dll from the author. For example, I know for sure where it comes from that there is the functionality I need, but I don’t know what it is and how to use it. Well, or more precisely. Let’s say the standard C library stdio.h is not .h but .so well or .dll. Let’s say I know that it has a function output to stdout. but what is it I don’t know about the function (printf). How can I find out what our imaginary stdio.so / .dll has the printf function. Now I’m not talking about how to use it later, although I would be happy with such information, I just started to master dll. I understand that standard dlls such as user32, kernel32 are described on MSDN. But what to do in the case of unknown ones from Vasya Pupkin.

Answer 1

I open IDA and see what kind of functions stick out, what parameters they take and what they do))

Answer 2

light artillery - eg DependencyWalker
heavy artillery - eg gdb

Answer 3

dumpbin -exports example.dll
but in the general case, do nothing, because in addition to the function, you need to know what arguments it has and what calling conventions are used, which in principle is not always possible.