Thread: Struct

Hello,

I'm looking at struct and I'm not sure what the difference between the following code:

Code:

   struct name {
      char *first;
      char *last;
   };

and putting 'typedef' at the start and some name afterwards is.

ie:

Code:

   typeset struct {
      char *first;
      char *last;
   } name;

Could someone please explain this to me?

Thanks

Um okay, which approach/style is better then?

Thanks

Personally i prefer using typedef before struct.........It gives more flexiblity. Lets see what others have to say about this?

Originally Posted by Mini

Um okay, which approach/style is better then?

Typedefs save us some typing (I guess this makes the latter approach 'better') and are commonly used in projects involving structs.

I've been trying to implement the first code into my function... where do I place it in the main function?

Sorry for this elementary question, but after reading 5 different sets of notes, I still have no clue...

Thanks

Put your definition of the struct in global space, right under your include file listings. That way all your functions can declare a local struct instance, as needed (it's common).

In main() declare the actual instance of the struct, itself, and a pointer to it. You'll probably want to pass around the pointer to it, to various functions. The advantage is that only functions that you pass the pointer to, will be able to change your struct (or array of structs if that's what you have instead of just one struct).

And it's typedef, not typeset.

Originally Posted by Adak

In main() declare the actual instance of the struct, itself, and a pointer to it. You'll probably want to pass around the pointer to it, to various functions.

Do I make a pointer to the whole struct (ie. 'myname') or to each individual 'component'?

And it's typedef, not typeset.

Thanks for that lol

To the whole struct. Then you can use the pointer to struct notation, that looks so fancy:

Code:

structPointerName->structMemberYouWant;

Very snazzy!

Hmm okay... does anyone have a link to a good tutorial covering this?

I'm not sure how to make a pointer to the struc...

Thanks alot for helping me with these rather elementary questions.

Hello,

Thanks for the tutorial but... here's my biggest area of misunderstanding... In the code:

Code:

   struct name {
      char *first;
      char *last;
   };

why are there dereferences? Whereas none of the notes and tutorials that I've read have it... this is the biggest area of my confusion atm

Originally Posted by Elysia

They are pointers. Do you understand pointers?

Yes I know pointers... but pointers need to point somewhere... and I'm not sure where/how to point them to.