Header files not found on Mac

I have a piece of code in C with header files included.
I run it on Mac OS X Maverick with XCode 4.6.2 installed. GCC is also installed. Note that Command Line Tools in XCode are already installed.

When I compile it, the error I receive says something like this:
add.c:1:19: error: stdio.h: No such file or directory
add.c:2:20: error: stdlib.h: No such file or directory
add.c:3:20: error: unistd.h: No such file or directory

However when I run it on Ubuntu, it compiles without a problem.


what to do?

Have you done a find or something to verify that the files do in fact exist on your system somewhere? If they do exist, then the problem is simply that your compiler/IDE (XCode in this case) is not setup properly to find the files where they are currently residing.

You should really be asking this question in a MAC or XCode specific forum however, and that is also where you would find the solution to pointing XCode to the current residence of your missing includes.

Such error messages (on any system) are typically a sign of a broken installation (of the compiler, library, etc) or of an incorrectly set environment variable (e.g. one that identifies the include path).