/* Fig. 5.12: fig05_12.c A scoping example */ #include void useLocal( void ); /* function prototype */ void useStaticLocal( void ); /* function prototype */ void useGlobal( void ); /* function prototype */ int x = 1; /* global variable */ /* function main begins program execution */ int main() { int x = 5; /* local variable to main */ printf("local x in outer scope of main is %d\n", x ); { /* start new scope */ int x = 7; /* local variable to new scope */ printf( "local x in inner scope of main is %d\n", x ); } /* end new scope */ printf( "local x in outer scope of main is %d\n", x ); useLocal(); /* useLocal has automatic local x */ useStaticLocal(); /* useStaticLocal has static local x */ useGlobal(); /* useGlobal uses global x */ useLocal(); /* useLocal reinitializes automatic local x */ useStaticLocal(); /* static local x retains its prior value */ useGlobal(); /* global x also retains its value */ printf( "\nlocal x in main is %d\n", x ); return 0; /* indicates successful termination */ } /* end main */ /* useLocal reinitializes local variable x during each call */ void useLocal( void ) { int x = 25; /* initialized each time useLocal is called */ printf( "\nlocal x in useLocal is %d after entering useLocal\n", x ); x++; printf( "local x in useLocal is %d before exiting useLocal\n", x ); } /* end function useLocal */ /* useStaticLocal initializes static local variable x only the first time the function is called; value of x is saved between calls to this function */ void useStaticLocal( void ) { /* initialized only first time useStaticLocal is called */ static int x = 50; printf( "\nlocal static x is %d on entering useStaticLocal\n", x ); x++; printf( "local static x is %d on exiting useStaticLocal\n", x ); } /* end function useStaticLocal */ /* function useGlobal modifies global variable x during each call */ void useGlobal( void ) { printf( "\nglobal x is %d on entering useGlobal\n", x ); x *= 10; printf( "global x is %d on exiting useGlobal\n", x ); } /* end function useGlobal */ /************************************************************************** * (C) Copyright 1992-2004 by Deitel & Associates, Inc. and * * Pearson Education, Inc. All Rights Reserved. * * * * DISCLAIMER: The authors and publisher of this book have used their * * best efforts in preparing the book. These efforts include the * * development, research, and testing of the theories and programs * * to determine their effectiveness. The authors and publisher make * * no warranty of any kind, expressed or implied, with regard to these * * programs or to the documentation contained in these books. The authors * * and publisher shall not be liable in any event for incidental or * * consequential damages in connection with, or arising out of, the * * furnishing, performance, or use of these programs. * *************************************************************************/