title: How to find a declaration of a variable/function in c code?
body: <p>Maybe it is a dummy question but for a long time I have been trying to read a C code written by others and each time unsuccessfully. When reading the code I stumble upon some macros or a function declaration of which I am just unable to find as they come from another libraries where it is not obvious from which one. For example, I stumbled on "STREQ" macros in <a href="http://git.savannah.gnu.org/cgit/coreutils.git/tree/src/cat.c" rel="nofollow noreferrer">cat.c</a> code which a source of "cat" tool and can't find its declaration in the code.</p>
  
  <p>So, the question is:</p>
  
  <p>Is there any way to find declarations of macros, functions within a code manually or using IDE features (which I am not aware of) without googling its name to check if it an STL function or not? How do you do it usually?</p>