This page describes some extra steps needed to use the SeeC compiler on OS X.
The C programs that you write are likely to require standard library header files or system header files. For OS X, the easiest way to get these is to install XCode.
When you are using SeeC's compiler, you will need to provide it the location of the header files. The exact location will depend on which version of OS X you are compiling for, but it should be within /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/. We provide the location of the appropriate SDK using the -isysroot argument. For example:
seec-cc -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk