[PLUG] gcc compilation issue

abhi abhi.elementx at gmail.com
Mon Jun 8 21:36:22 IST 2009

Hi all. I am trying to learn writing linux modules. I am referring to a book
for writing the modules in C.
my code is :
#include <linux/module.h>  /* Needed by all modules */
#include <linux/kernel.h>  /* Needed for KERN_ALERT */
int init_module(void){
   printk("<1>Hello world 1.\n");
   return 0;

void cleanup_module(void){
  printk("<1>Goodbye world 1.\n");

when I compile this using :
$ gcc -c hello-1.c

It says :
hello-1.c:4:55: error: linux/module.h: No such file or directory
hello-1.c: In function ‘cleanup_module’:
hello-1.c:19: error: ‘KERN_ALERT’ undeclared (first use in this function)
hello-1.c:19: error: (Each undeclared identifier is reported only once
hello-1.c:19: error: for each function it appears in.)
hello-1.c:19: error: expected ‘)’ before string constant

how do i solve this?
Thank you.

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