Sams Teach Yourself C in 21 Days

Advanced Program Control 325

13

37: delay();

38: break;

39: }

40: case 4:

41: {

42: puts(“\nExecuting task D.”);

43: delay();

44: break;

45: }

46: case 5: /* Exit program. */

47: {

48: puts(“\nExiting program now...\n”);

49: }

50: default:

51: {

52: puts(“\nInvalid choice, try again.”);

53: }

54: } /* End of switch */

55: command = menu();

56: } /* End of while */

57: return 0;

58: }

59:

60: /* Displays a menu and inputs user’s selection. */

61: int menu(void)

62: {

63: int reply;

64:

65: puts(“\nEnter 1 for task A.”);

66: puts(“Enter 2 for task B.”);

67: puts(“Enter 3 for task C.”);

68: puts(“Enter 4 for task D.”);

69: puts(“Enter 5 to exit program.”);

70:

71: scanf(“%d”, &reply);

72:

73: return reply;

74: }

75:

76: void delay( void )

77: {

78: long x;

79: for( x = 0; x < DELAY; x++ )

80: ;

81: }

LISTING13.7 continued

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