title: How to add a default include path for GCC in Linux?
body: <p>I'd like gcc to include files from <code>$HOME/include</code> in addition to the usual include directories, but there doesn't seem to be an analogue to <code>$LD_LIBRARY_PATH</code>.</p>
  
  <p>I know I can just add the include directory at command line when compiling (or in the makefile), but I'd really like a universal approach here, as in the library case.</p>