Re: 'hello world' module

[Jesper Juhl <jesper.juhl@gmail.com>]

On 6/11/05, Ilan S. <ilan_sk@netvision.net.il> wrote:
> Hello dear professionals!
> 
> I would be very thankful if anybody prompt me what's wrong.
> I'm trying to build the "Hello world" module from O'Reilly's "Linux device
> drivers" and that is what I get:
> 
I don't have that book, so I can't really say, but here's an example
from "Linux Kernel Development, 2ed" by rml
(http://rlove.org/kernel_book/)


/*
 * hello.c - Hello, World! As a Kernel Module
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>

/*
 * hello_init - the init function, called when the module is loaded.
 * Returns zero if successfully loaded, nonzero otherwise.
 */
static int hello_init(void)
{
        printk(KERN_ALERT "I bear a charmed life.\n");
        return 0;
}

/*
 * hello_exit - the exit function, called when the module is removed.
 */
static void hello_exit(void)
{
        printk("KERN_ALERT "out, out, brief candle!\n");
}

module_init(hello_init);
module_exit(hello_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Shakespeare");


To build the module above, make a Makefile in the same dir with this
line in it :

obj-m := hello.o


Then build like this:

make -C /kernel/source/location SUBDIRS=$PWD modules


Works for me :)

Of course there's lots of additional info in the book. Robert wrote a
rather good one, it's well worth checking out if you ask me.


-- 
Jesper Juhl <jesper.juhl@gmail.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please      http://www.expita.com/nomime.html