ascii to pointer?

[Khanser]

I'm recalling the gurus of C: is any way of converting from a string that contains the address of a pointer to the pointer? Everything would be fine if "atoh()" would exist =_=.

void * mail;
mail = map_mem(ipc_mail);
int * arr_mail;
arr_mail = atoh(mail*); <--- ??!?!?!

mail contains a (char *) within is stored the value of a pointer in ascii like this :

int arr_mail[9];
void * mail;
mail = map_mem(ipc_mail);
sprintf(mail,"&#37;p",arr_mail);

PS: Sorry about my english and thanks to everone

[matsp]

sscanf(mail, %p", &ptr) perhaps? [I haven't tried it].

Otherwise you should be able to use "%x" or "%lx" - pointers are normally convertable to long integers.

--
Mats

[Khanser]

Oh, fast reply! Thanks!!

I will try it out

[matsp]

Of course, this sort of begs the question "Why the **** are you doing this?"

There is really no good reason to convert a pointer to a string and then to convert it back to a pointer again - pointers are generally only valid within their own process, so there's no reason to make pointer to text so that you can send them across a network, which is the most common reason to convert a binary value to text.

So whilst my previous post may have given you a solution, the question I should have asked in the response should have been "Are you sure you want to do that?".

--
Mats

[Khanser]

int arr_mail[9];
mail = map_mem(ipc_mail);
sscanf(*mail,"&#37;p",arr_mail);

Compier says:

warning: passing arg 1 of `sscanf' makes pointer from integer without a cast

Damn, that was close >_<



Answering on your question: I am doing a multi-process program and i MUST use the (map_mem) function but I don't want to make the execlp() with 9 parameters, and later use it 9 times for the array that i have. So i make an IPC i give the array to the IPC and i only have the "execlp" with 1 parameter.

(I'm not used to computer language at english so if you don't understand what i'm trying to say, ask, and i will try to explain it the best i can :/)

[matsp]

You should not have a star on the first argument to sscanf(). That is the pointer to the string you are reading your data from.

--
Mats

[Khanser]

without the star:

warning: passing arg 1 of `sscanf' from incompatible pointer type

Well the pointer at string format is within the pointer so i think the star would be at good place right?
(I'm a baddass n0b with pointers)

[matsp]

Ah, yes, your mail is a void pointer, isn't it. Casting it like this should work:

sscanf((char *)mail, ...)

--
Mats

[Khanser]

Lol, thank you very much.