Stupid struct question

PhantomBeaker

Hey,

Just a very quick question. I'm doing some stuff in C, and I'm currently muddling my way through this (i.e. learning as I go, and gleaning of as many tutorials as I can find).

The thing is, the tutorials aren't answering one pretty big question for me. How do I drop a structure once I'm finished with it? Do I just call free(whatever) ?

Also, if I'm doing this in C++, and still using structs for some odd reason (like I'm working on a project with mixed code, and I'm using a function that returns a struct) could I also use delete, or would it be best to stick with free or some other solution?

Thanks,
Aoife

Torak

PhantomBeaker wrote:

Hey,

Just a very quick question. I'm doing some stuff in C, and I'm currently muddling my way through this (i.e. learning as I go, and gleaning of as many tutorials as I can find).

The thing is, the tutorials aren't answering one pretty big question for me. How do I drop a structure once I'm finished with it? Do I just call free(whatever) ?

Also, if I'm doing this in C++, and still using structs for some odd reason (like I'm working on a project with mixed code, and I'm using a function that returns a struct) could I also use delete, or would it be best to stick with free or some other solution?

Thanks,
Aoife

AFAIR struct and class are interchangable in C++ except that in struct members default to public instead of private...

the term struct was only retained for compatibility with C and essentially means a class which members default to public.. you can even declare constructors and destructors!

bpmurray

In C you use malloc or calloc to allocate space for your structure, and use free to return that piece of memory to free space. In C++ you're free to use delete or free, but it's good practice to pair new with delete and c/malloc with free.

rmacm

As bpmurray said use malloc in C to allocate space for structures and then use free to return the memory to the available free space. The way we were taught in college using C++ was to use the new and delete keywords and make sure you pair them as mentioned.

Torak structs and classes are not the same thing. Structs are data structures well at least as far as we were shown in college. Structs don't contain any methods on the data they contain which would make them different to classes.

Cheers
Rory

Torak

rmacm wrote:

Torak structs and classes are not the same thing. Structs are data structures well at least as far as we were shown in college. Structs don't contain any methods on the data they contain which would make them different to classes.

Cheers
Rory

http://www.research.att.com/~bs/glossary.html

Stroustrup wrote:

struct - class with members public by default. Most often used for data structures without member functions or class invariants, as in C-style programming. TC++PL 5.7, 10.2.8, D&E 3.5.1.

Considering he invented the language I will take his word over yours..
:cool:

Smellyirishman

That's basically what rmacm said.

Torak

Smellyirishman wrote:

That's basically what rmacm said.

:eek:

read it again..

"most often" does not mean "don't"

idioms and usage patterns are not syntactical rules

The definition given by stroustrup is identical to the information originally furnished by me and questioned by rmacm.

:cool: