struct sigaction incomplete error

Question

Although including I get an error saying that struct sigaction is an incomplete type.

I have no Idea what to do with it.

Answer 1

I resolved this by changing the C standard that I was using with gcc.

I changed: gcc -std=c99 ...

to this: gcc -std=gnu99 ...

Answer 2

Just

#define _XOPEN_SOURCE 700

before any other line in your code, or compile with the -D option to define the preprocessor symbol

gcc ... -D_XOPEN_SOURCE=700 ...