Procedures

• There is a special kind of function that returns no value. In the computer science literature, these are normally called procedures.

• In C, procedures are just functions which the special type void. All return statements in a void function should look like this: return;. Void functions should never be called in an expression.

• Here is an example:

  void printDirections()
  {
    printf( "Press h for help, n for next page, b for previous page.\n" );
    return;
  }
  

• In contrast to functions, procedures having side effects are a good thing! If you can, try to make all of your subroutines that have side effects be procedures and all of the other ones functions.