/* ----------------------------------------------------------------------  
//   Figure 6.19:  Using a delay loop.                                     
//   Figure 6.20:  Delaying progress, the delay() function.                                     
// ---------------------------------------------------------------------- 
//   Note: The delay function is defined in the tools library, which is 
//      included here.  A copy of the code is given below, enclosed in a 
//      comment so that it will not interfere with compilation and linking.
*/
#include "tools.h"

void main ( void )                              
{
    int j, max, seconds;          

    printf( "This is an exercise program.\n\n"    
            "How many pushups are you going to do? " );    
    scanf( "%i", &max);                               
    if (max < 0) fatal( "Can't do %i pushups!", max );

    printf( "How many seconds between pushups? " );          
    scanf( "%i", &seconds );                              
    if (seconds < 3) fatal( "Can't do a pushup in %i seconds!", seconds );

    printf(  "OK, we will do %i pushups, one every %i seconds.\n" 
             "Do one pushup each time you hear the beep.\n", max, seconds );

    for (j = 1; j <= max; ++j) {                             
        printf( "%i \a\n", j );     /* Do one. */  
        delay( seconds );           /* Now wait specified # of seconds. */ 
    }   

    puts( "Good job.  Come again." );   
}

/* -------------------------------------------------------------------------- */
// Delay progress of program for some number of seconds using a "busy wait".   
#include <time.h> 
void 
delay( int seconds )
{   
    time_t goal = time( NULL ) + seconds;  
    do { /* Nothing */ } while (time( NULL ) < goal);    
}