printk is not my friend

Charles Brown charles.brown at
Mon Apr 5 16:39:53 UTC 2010

i'm sorry to bother you with this, but i've been chasing my tail through 
LDD3 and forum posts for hours with no luck, so i figure ask some 
experts. i have a typical 'hello world' module, on off-the-shelf ubuntu 
karmic, and can not get it to printk anything, anywhere, anyhow. i 
assume my problem is trivial, but i can't find it.  i've tried;

static int __init init(void) {
     printk(KERN_DEBUG "Hello, world\n");

static void __exit exit(void) {
     printk(KERN_DEBUG "Goodbye, cruel world\n");

apt-get install klogd,
echo 7 > /proc/sys/kernel/printk
/etc/init.d/sysklogd restart

every flavor of printk(KERN_DEBUG/CRIT/EMERG/INFO/ALERT

and more things from various forums posts

all the while with a tail -f /var/log/kern.log running.

is there a step-by-step for 'hello world' someplace? suggestions?

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