The Pets Project

• basics.h which defines the types boolean and name_t. Note the #ifndef...#endif wrapped around the body, to prevent it from being #included more than once.
• cat.h which defines the cat struct type.
• fish.h which defines the fish struct type.
• dog.h which defines the dog struct type, and also provides a prototype for the collect_bones function. Note that this, too, has an #ifndef...#endif wrapped around it to prevent multiple inclusion.
• dog.c which defines the collect_bones function.
• pet.h defines the pet_kind enum and the pet struct. This could have had an #ifndef...#endif wrapped around it; in this project, we didn't need to, but it doesn't hurt, and might save a lot of trouble in a future project.
• pet.c A main program and a pseudo-polymorphic function on pets.
• MAKEFILE An ordinary text file specifying dependencies among the files. For example, pet.exe can't be built until pet.obj and dog.obj exist and are up to date; if one of them has changed recently, you need to re-link. Similarly, pet.obj needs to be rebuilt if any of pet.c, pet.h, or dog.h has changed recently.