From PHP to C

[Kudose]

Does anyone know of any good tutorials about learning C after knowing PHP? I suppose a PHP to C++ tutorial would be alright too, but I am more interested in ANSI C.

I seem to be struggling on pointers ... one of the main differences between C and PHP.

I've read tons about them, but I just don't get when to use them and why and what not. Something with examples of code would be preferable.

Thanks. 🙂

[laserlight]

I am more a C++ programmer than a C programmer, but I would say that pointers would commonly be used when you need a dynamic array (malloc() returns a pointer) and when you need to pass by reference. Since C only has pass by value, you would need to pass a pointer by value to simulate pass by reference.

Note also that arrays decay to a pointer to their first element when passed as an argument. Consequently, things like sizeof() would be working on the pointer, not the array, under some circumstances, even though you are dealing with an array.

[NogDog]

Ugh. I share your pain, as I was never comfortable with pointers with the little bit I ever did in C. Whenever I ran into them in someone else's code, I usually had to dig up a reference and re-read it a couple times until (hopefully) I figured out what the code I was reading was trying to do. For whatever reason it just never sunk itno my brain. :rolleyes:

[Kudose]

Laserlight, why can't you just pass the address of the variable?

In my mind, a pointer is needed to stop pass-by-value. So couldn't I just pass an address and use pointers in the function?

[laserlight]

Laserlight, why can't you just pass the address of the variable?

You do. A pointer holds an address. Consider a function with this prototype:

void foo(int*);

To call and pass it an int variable num, you might write:

foo(&num);

& is the address-of operator.