question about local variables and function parameters

[Guest_imported]

If you declare a local variable that's a C array, you have to specify the number of elements in the array. On the other hand, if you declare a function parameter that's a C array, you don't have to specify the number of elements. Why the difference?

 

[CaKiwi]

Hi Iemonslice

When you declare a local variable, the compiler must reserve memory for it and so must know what size it is. But when a function receives a variable as an argument, the memory has already been reserved by a calling function and so you don't need to specify the size.

Hope this helps.

CaKiwi

 

[Guest_imported]

thx =)

 

[smaniraja]

while declearing an array your have specify the number of elements because memory will be allocated on that time. But while passing the array your are passing the address of the array and while receiving its just a pointer variable, the required memory for pointer variable is fixed ( 2 or 4 byes).

Maniraja S