Sams Teach Yourself C in 21 Days

Using Disk Files 447

16

16: for (count = 0; count < 5; count++)

17: scanf(“%f”, &data[count]);

18:

19: /* Get the filename and open the file. First clear stdin */

20: /* of any extra characters. */

21:

22: clear_kb();

23:

24: puts(“Enter a name for the file.”);

25: gets(filename);

26:

27: if ( (fp = fopen(filename, “w”)) == NULL)

28: {

29: fprintf(stderr, “Error opening file %s.”, filename);

30: exit(1);

31: }

32:

33: /* Write the numerical data to the file and to stdout. */

34:

35: for (count = 0; count < 5; count++)

36: {

37: fprintf(fp, “\ndata[%d] = %f”, count, data[count]);

38: fprintf(stdout, “\ndata[%d] = %f”, count, data[count]);

39: }

40: fclose(fp);

41: printf(“\n”);

42: return 0;

43: }

44:

45: void clear_kb(void)

46: /* Clears stdin of any waiting characters. */

47: {

48: char junk[80];

49: gets(junk);

50: }

Enter 5 floating-point numerical values.

3.14159

9.99

1.50

3.

1000.0001

Enter a name for the file.

numbers.txt

data[0] = 3.141590

data[1] = 9.990000

data[2] = 1.500000

data[3] = 3.000000

data[4] = 1000.000122

LISTING16.2 continued

INPUT/

OUTPUT

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