Quick Question

[topherpunch]

Just had a quick question about a certain reference. <cerrno> (errno.h)

Just wondering how much this is used during programs? I honestly have never seen it.

[Peter87]

I use it sometimes to catch mistakes made by the programmer. If I have function that assumes that a parameter is not null assert(p != nullptr); or within some range assert(pos < size); etc. Never use it to catch invalid input from the user! assert can be disabled by defining the macro NDEBUG so I don't have to pay the cost of these checks when running the real thing.

[topherpunch]

So do you only use it with the assert function?

Also can you show me a short way to use it?

[Peter87]

Haha ops... My eyes must be getting old. I somehow thought you wrote <cassert>. Well, in that case just ignore what I said.

I have never used errno in C++. I think I have used errno in C but I don't remember really and I don't use C much. I think there are often better ways to signal errors than to use errno.