Sample Output -I/usr/local/Cellar/gnutls/3.5.8/include -I/usr/local/Cellar/nettle/3.3/include -I/usr/local/Cellar/libtasn1/4.10/include -I/usr/local/Cellar/p11-kit/0.23.3/include/p11-kit-1Īnd the linker library settings with: pkg-config -libs gnutls Then, once you have that, you can find the compiler include file settings with: pkg-config -cflags gnutls So, you need to install pkgconfig if you don't have it already using: brew install pkgconfig It seems that GNUtls, as installed by homebrew ships with a pkgconfig file.