Veriable problem

Hi everybody,

in a .h header file
i want to declare a var as

extern struct mytype a[200];


after I include the header file in a dot c file


and define the var in the global scope of the dot c file as

struct mytype a[200];

but the compiler
complains the redefinition occurs,

how to cope with it? thanks in advance.

 

in the h header file, i also tried declare the var as
extern struct mytype *a;

it differs nothing.

I know if in .h file

i declare
extern int a;

in dot c file,
i define
int a = 1;

it would ok, why??

what's difference between the two variables?

 

in a .h header file
i want to declare a var as

extern struct mytype a[200];

after I include the header file in a dot c file
and define the var in the global scope of the dot c file as

struct mytype a[200];

but the compiler complains the redefinition occurs,

Where have you defined struct mytype?