First kernel module (2.6 kernel) - hello

/* First kernel module - hello.c */

/*
--------------------------------------
Steps to be followed
#vi hello.c - Enter the given c code
#vi Makefile - Enter the following
obj-m += hello.o
all:
make -C /lib/modules/$(shell uname -r)/build M=$(shell pwd) modules
clean:
make -C /lib/modules/$(shell uname -r)/build M=$(shell pwd) clean
install:
make -C /lib/modules/$(shell uname -r)/build M=$(shell pwd) modules_install
#make
#insmod hello.ko
#dmesg tail -4 --> view message
#rmmod hello
#dmesg tail -4 --> view message
--------------------------------------
*/

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

static int __init hello_init(void)
{
printk(KERN_INFO "Hello world\n");
return 0;
}

static void __exit hello_exit(void)
{
printk(KERN_INFO "Goodbye world\n");
}

module_init(hello_init);
module_exit(hello_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("KERNO");
MODULE_DESCRIPTION("First kernel module");

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