Thread: Clearing thought on pointer usage ?

Hi,
to everybody

I am using C language since few months. I have learnt C at my bachelor Engg. But since then I have not been using it.

I have some doubt on pointer usage.

Can anyone tell me when to pass address as an arguments to function and when to pass pointer as an argument to the function?

If you can explain with example it will be great...or any link to this particular doubt will be very helpful.

Thanks in advance.

Can anyone tell me when to pass address as an arguments to function and when to pass pointer as an argument to the function?

Well, an address is a pointer's value. A pointer is supposed to hold the memory address of an object of a certain type, and this type is expressed when you declare a pointer, i.e.

Code:

int *p;
int **q;

Like this, *p is an int, and *q is an int*.

So now that we know the type of pointer, say you have a function that expects an int * in the argument list. You have two things you can pass in. If you have an int, you can pass it's address (&foo). If you have a pointer, you can just write the variable name (p).

Does this help.