#include <stdio.h>

#include "shared.h"

/*
 * driver.c -- demonstrates the use of header files, and type qualifiers
 */

int main ( int argc, char *argv[] )
{
   // call an exported function by shared.c through shared.h 
   greeting();

   // what is the current altitude
   print_altitude();  // print_altitude is exported through "shared.h" (no compiler warning)

   // let's go down a bit
   descend(500.0);    // descend is not declared in "shared.h", but we know it is there! (compiler warning)

    // let's go up now
    // ascend(500.0);    // ascend is declared static (gives compilation error)

   // where we are now 
   print_altitude();

   // wherever we are, let's go up twice as high
   altitude *= 2.0;  // we can meddle with global variables however we like

   // where we are now 
   print_altitude();

   //printf("speed is %g mph\n", speed);   // speed is defined in shared.c, but not exported, and is invisible

   return 0;
}