Re: [linuxiran] [OT] C programming, variable size array

[Hossein S. Zadeh]

On Fri, 12 Dec 2003, Aryan Ameri wrote:

> int tmp, cnt = 0;
> static int arr[cnt];
> printf( "Enter Number\n");
> scanf( "%d", &tmp);
> while ( (tmp = getchar() ) != EOF ) {
>         arr[cnt] = tmp;
>         cnt += 1;
>         static int arr[cnt];
>         printf( "Enter Number\n");
>         scanf( "%d", &tmp);
> }
> 
> return 0;
> }
> 
> This sounded logical to me. But the compiler (gcc 3.2) gives me a syntax 
> error saying that 'storage size of 'arr' isn't constant'. Well, I don't 
> want it to be constant!

Hi there,
This is obviously wrong. Array sizes are needed (by C compilers) during 
compile time. This is the single most cause of buffer overflows in C and 
C++ programs. 

What you need is a "linked list". You can find examples in any C book you 
find in your nearest book shop or library.

cheers,
Hossein