int mount; auto
int month;

}

The example above defines two variables with in the same storage class. 'auto' can only be used within
functions, i.e., local variables.

The register Storage Class

The register storage class is used to define local variables that should be stored in a register instead of
RAM. This means that the variable has a maximum size equal to the register size (usually one word) and
can't have the unary '&' operator applied to it (as it does not have a memory location).

{

register int miles;

}

The register should only be used for variables that require quick access such as counters. It should also be
noted that defining ‘register’ does not mean that the variable will be stored in a register. It means that it
MIGHT be stored in a register depending on hardware and implementation restrictions.

The static Storage Class

The static storage class instructs the compiler to keep a local variable in existence during the life-time of
the program instead of creating and destroying it each time it comes into and goes out of scope.
Therefore, making local variables static allows them to maintain their values between function calls.

The static modifier may also be applied to global variables. When this is done, it causes that
variable's scope to be restricted to the file in which it is declared.

In C programming, when static is used on a global variable, it causes only one copy of that member to be
shared by all the objects of its class.

#include

/* function declaration */ void func(void); static
int count = 5; /* global variable */ main() {
while(count--) { func(); ) return 0;

}

static int i = 57/* local static variable ١

printf("i is %d and count is %d\n", i, count);