c creating header files

Creating Header Files:

Step1:

Confirm the Convention to be used to ‘include’ the header file.

# include <stdio.h> (OR) #include “stdio.h”

If the First Version is chosen then the HEADER FILE must be in the INCLUDE

DIRECTORY.

If the Second Version is chosen then the HEADER FILE must be the SOURCE

DIRECTORY.

Step 2:

Open a NEW FILE and write DEFINITIONs of ALL FUNCTIONS, which are

required to be part of the Header File.

Step 3 :

Save the FILE in the INCLUDE DIRECTORY (OR) in the SOURCE DIRECTORY.

Step 4:

Make use of the header file is any Program wherever the need arises.

The Contents of our Header File.

int fact(int n)

{

int x, j;

for(j = 1, x = 1; j <= n; j++)

x = x * j;

return(x);

}

int primecheck(int x)

{

int j, flag = 0;

if(x == 0 || x == 1)

flag = 0;

else

if(x == 2)

flag = 1;

else

{

for(j = 2; j < x / 2; j++)

{

if(x % 2 == 0)

{

flag = 0;

break;

}

else

flag = 1;

}

}

if(flag == 1)

return 1;

else

return 0;

}

long int power(int x, int y)

{

long int pow;

int k;

for(k = 1, pow = x; k <= y; k++)

pow = pow * k;

return(pow);

}

int checkvowel(char ch)

{

if(ch == 'a' || ch == 'c' || ch == 'i' || ch == 'o' || ch == 'u' || ch == 'A' || ch == 'E' ||

ch == 'I' || ch == 'O' || ch == 'U')

return (1);

else

return(0);

}

Save the file as Myfunc.h

Using the CONTENTS of the HEADER FILE

Program

#include<stdio.h>

#include "F:\Vc\\PROGHE~1.h"

void main()

{

int choice = 0, num, a, b;

char ch;

do

{

printf("\nMain Menu Functions.");

printf("\n1.Check Vowel ");

printf("\n2.Prime Check ");

printf("\n3.Power ");

printf("\n4.Factorial ");

printf("\n0.Exit ");

printf("\nEnter Choice[0..4]: ");

scanf("%d", &choice);

switch(choice)

{

case 1: printf("\nEnter Any Character : ");

fflush(stdin);

scanf("%c", &ch);

if(checkvowel(ch))

puts("It is a Vowel.");

else

puts("It is Not a Vowel.");

break;

case 2: printf("\nEnter Any Value : ");

scanf("%d", &num);

if(primecheck(num))

printf("It is Prime Number.");

else

printf("It is Not a Prime Number.");

break;

case 3: printf("\nEnter Any Two Positive Values : ");

scanf("%d%d", &a, &b);

printf("\nThe Result is : %d", power(a, b));

break;

case 4: printf("\nEnter Any Positive Value : ");

scanf("%d", &num);

printf("\nThe Factorial is : %d", fact(num));

break;

case 0: printf("\nThank You...");

}

}while(choice > 0);

}