Re: [NEWBIE] Arrays

From: Bill Long (wlong@E-SERVER.NET)
Date: 10/27/98

Not sure if i understand what you are wanting. but here is just a little more
lets say you have a struct declared as so..
struct my_kewl_struct_type {
}  kewl_struct;

you have but two ways you can declare an array of these fellas.
the first is statically:
  struct kewl_struct mks[20];
which will give you a fixed size array of structs. even if they are all empty.
You can also declare an array of POINTERS to the struct and then create/destroy
the structs as you need them. like so...
  struct kewl_struct *mks_ptr[20]; //allocate an array of POINTERS(not structs)

  CREATE(mks_ptr[10], struct kewl_struct, 1);  //the CREATE macro is a fancy
                                               //calloc with error checking
   //the above will create a struct kewl_struct at the 11th position in the
   //mks_ptr array(i know..this is KINDOF dynamic..)
  free(mks_ptr[10]);  //frees the space allocated for the struct but the
                      //pointer is still there(it was declared statically)

the second is dynamically.

  struct kewl_struct *first_kewl_struct;

  CREATE(first_kewl_struct, struct kewl_struct, 1);
    //this creates a reference to ONE structure of type kewl_struct complete
    //with allocated populating space.( achieves same result as
    //struct kewl_struct first_kewl_struct (only with different ways of
    //the structure.

  CREATE(first_kewl_struct, struct kewl_struct, 20);
    //this creates a reference to MANY structures of type kewl_struct complete
    //with allocated populating space. but you must use POINTER arithmetic or
    //array notation to get to the other ones. ie (first_kewl_struct + 5) will
    //get you to the structure in the 6th position of the of the array.(i'll
    //calle it a table) or first_kewl_struct[5] (achieves the same result)

i'm pretty sure that these are the only ways to declare arrays(sure, there are
variations).  i hope this helps a bit.  i would also recommend that you really
spend some bucks and get a C book. Pointers are one of the foundations of the C
language. if you dont understand them you will spend literally HOURS sifting
through code trying to understand what is going on.

also, double check this against your books, i dont have any in front of me right

now so this is all from memory, there are probable errors.

Jourge Fuzz Bush wrote:

> No. There is quite a difference from what george wrote and what I was
> looking for. I will admit I didn't understand it fully (the create). But
> after taking a look at the code for the create macro there arose to many
> problems that a simple static array would fix. I was looking for an
> answer that did not require me to "explicitly" define the size because I
> didn't really want to put a cap limit on the number of people who can
> die without reclaiming there bodybags and I didn't want to waist memory
> that wasn't used. But I guess I will have to write some clean-up
> procedures based on time of death and time on the mud. I think I even
> did try defining the size of the array "explicity" but it didn't work. I
> must have messed it up somewhere along the line. But thankyou everyone
> for your help.


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