File example
#include<stdio.h>
#include<stdlib.h>
/* must use this library to use exit program */
/* Chapter 11 page 437 #7 */
int main()
{
FILE *cars; /* declare that cars is a file */
int car, miles,
gallons, mpg;
cars = fopen(“A:auto.txt”,”r”); /*
open cars for reading – this file is called auto.txt on the A drive */
if (cars == NULL)
/* test if the file exists */
{
printf(“\nFailed to open file. \n”);
exit(1);
}
printf(“\t Car Data ”);
printf(“\n Car \t Miles \t
Gallons \t MPG”); /* print heading for
output */
while (fscanf(cars,”%2d %4d
%2d”,&car,&miles,&gallons) != EOF)
/* read from file cars the
car number, the miles traveled and the gallons until end of file found */
{
mpg=miles/gallons;
printf(“\n %2d \t %4d \t %2d \t %2d”,car,miles,gallons,mpg);
}
fclose(cars); /*close the car file */
return 0;
}
Input file – entered in Notepad, saved
as auto.txt
54025019
62052538
710123 8
85132286
97023514
Program Output
