External Storage Class
When you are declaring the variables as external storage class, it is accessed in all the functions which is defined in the same program. The variables are called extern or global variables. External variables are declared outside the function body. In case both external and auto variables are declared with the same name in a program the first priority is given to the auto variable. In this case external variable remain hidden.
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S.No.
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Features of External Variable
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Meaning
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1.
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Storage or location of variable
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Memory
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2.
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Initial or default value
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Zero
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3.
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Scope of the variable
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Global
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4.
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Life of the variable
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As long as the program's execution doesn't come to the end of the program.
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Example of External Storage Class
#include<stdio.h>
#include<conio.h>
int num=5;
main()
{
int num=20;
printf("\t%d",num);
display();
}
display()
{
printf("\t%d",num);
}
Output: 20 5
Explanation: In this program, first the value of local variable is printed i.e. 20. When display () function is called it will print the global value of variable num i.e. 5.