Figuring out who installs errno

Question

Is there any way to find out in which function / file / line the current errno is set?

Answer 1

I don't know what I know, it's just a global static int (no magic) (see comment below).

You should check after every function that could install it when it returns an error.

Answer 2

Unfortunately, not programmatically.

Just a thought: if this is a debugging problem, perhaps you can set a memory breakpoint at the address where errno is stored and cause it to break when it is written to memory. Then the call stack will tell you who did it.