Re: [Nasm-users] a quick question:

[Frank K. <fbk...@zy...>]

Tyler Littlefield wrote:
> Hello,
> I'm going to try to write a "guess the number." tyep program.
> First, I wrote this, so I could link to it:
> #include <cmath>
> #include <ctime>
> #include <cstdlib>
> int rnum();
> int rnum()
> {
> srand(time(NULL));

I think you want to only do this once.

> return (rand()%10);
> }
> I'm also going to have to write a rapper for itoa.
> next, my asm program so far is as follows:
> global _start
> section .text
> welcome db "Welcome to guess the number!",10,"Written by Tyler Littlefield 
> <ty...@ty...>",10,10
> welcomelen equ $-welcome
> texta db "I am thinking of a number between 1 and 10.",10,"Can you guess it 
> in three tries?",10
> textalen equ $-texta
> section .data

You've got "section .text" and "section .data" swapped!!!

> nop
> _start:
> nop
> mov eax,4
> mov ebx,1
> mov ecx,welcome
> mov edx,welcomelen
> int 80h
> mov eax,4
> mov ebx,1
> mov ecx,texta
> mov edx,textalen
> int 80h
> when I compile with nasm, that works great. but when I gcc ns.o rand.o it 
> gives errors about _start,

"_start" exists in the C "startup" code (crt0.o?), and we only want one 
- this calls "main", so start your asm code with "main" nd has to be 
declared global), not "_start". Or link with "ld -o myprog ns.o rand.o 
-I/lib/ld-linux.so2 -lc".

> and then says it can't find time and srand and 
> rand.
> Ideas?

Dunno about that one. I thought those were "standard"... shouldn't need 
underscores... Dunno. Jeff Duntemann's got a "rand()" example in 
linuxcode.zip from:

http://www.copperwood.com/pub/

I'm "working on" (figure of speech) a reply from a couple messages ago 
with a few simple C/asm examples... I'll get back to ya "real soon now"...

(incidentally, to reply to this list, hit "reply all" - just "reply" 
replies only to the sender - I'm not sure the message I refer to 
actually made it to the list...)

I'll get back to ya - and see my post on the forum... might help...

Best,
Frank