Q5 Write a C program to show the storage, default initial value, scope and life of a external storage class variable.

Program: 143

Write a C program to show the storage, default initial value, scope and life of external storage class variables.

Variable Storage Class tells us:

1. Storage (location)
2. Default Initial Value of the variable
3. Scope of the variable
4. Life of the variable

1. Storage: Where the variable would be stored.

2. Default Initial Value: What will be the initial value of the variable, if initial value is not specifically assigned. (i.e. the default initial value)

3. Scope: What is the scope of the variable: i.e. in which functions the value of the variable would be available.

4. Life: What is the life of the variable: i.e. how long would the variable exist.

External Storage Class:

Same as Static Storage Class but the life of the variable exists till the program’s execution does not come to end.

Storage : Memory
Default Initial Values : Zero
Scope : Global
Life : As long as the program’s execution doesn’t come to end.

#include<stdio.h>
int i; //external storage class variable
void increment();
void decrement();
int main()
{
    printf("\ni=%d\n",i);
    increment();
    increment();
    decrement();
    decrement();
    return 0;
}

void increment()
{
    i=i+1;
    printf("On incrementing i = %d\n",i);
}

void decrement()
{
    i=i-1;
    printf("On decrementing i = %d\n",i);
}

Output:

i=0
On incrementing i = 1
On incrementing i = 2
On decrementing i = 1
On decrementing i = 0