How to find right header files when multiple versions are exist

[John Graham]

> How can I found that which stdio.h is compiler looking for?

Pass the --verbose flag to gcc, and you'll get something like this
(amongst other output):

$ gcc program.c --verbose
(...)
ignoring nonexistent directory "/usr/local/include/i486-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../i486-linux-gnu/include"
ignoring nonexistent directory "/usr/include/i486-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
 /usr/local/include
 /usr/lib/gcc/i486-linux-gnu/4.4.1/include
 /usr/lib/gcc/i486-linux-gnu/4.4.1/include-fixed
 /usr/include
End of search list.
(...)


John G
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