Hello friends

I'm using Redhat 9.0 and i want to start the kernel programming
but as it is different the case i'm not getting how to compile modules and running them so i read one e-book and wrote the "hello world" module
and tried to compile by making make file
but it is giving error like "Nothing to be done for all"

i'm not getting please help me i'm writing my program and make file below

****************Hello.c***************************

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

int init_module(void)
{
printk(KERN_ALERT "\nHello Kernel\n");
return 0;
}
int cleanup_module(void)
{
printk(KERN_ALERT "\nGoodbye kernel\n");
}


*********** Makefile*****************************

obj -y+=hello.o

all:
gcc -C /lib/modules/$(shell uname -r)/build/M=$(PWD) module

clean:

gcc -C /lib/modules/$(shell uname -r)/build/M=$(PWD) clean


please help me and please tell me if there is a good book of kernel programming.

thanx in advance.

I have heard this is "the" book;
http://rlove.org/kernel_book/

well pratik this is the problem that everyone who starts kernel programming is bound to face.
you can refer to Rubinni's "Linux Device Driver" or can go through LKMPG available online at tldp.org.
This is a sample makefile for the hello world program,which i used for my hello world program.

TARGET := hello
INCLUDE := /usr/src/linux-2.4.20/include
CFLAGS := -I$(INCLUDE) -O -Wall

$(TARGET).o:$(TARGET).c

clean:
rm -rf $(TARGET).o

hope this is self-explanatory.

Hello Jasdeep Thank you for that make file. it really worked. But as i used to experiments with my PC and Operating system i've just recompile my kernel of redhat 9.0

and now i'm getting another error whenever i compile a module it get compiles successfully
but at the time of insertion it gives error like "version Mismatch error"
it is compiled for 2.4.20-8custom while the kernel version is 2.4.20-8
i tried in both the kernels but i'm getting same error. then
i read some sources and modified the code as belows

i tried some code that


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

#if CONFIG_MODVERSIONS==1
#define MODVERSIONS
#include <linux/modversions.h>
#endif


MODULES_LICENSE("GPL"); /* removes license warning*/
int init_module(void)
{
printk(KERN_ALERT "\nHello Kernel\n");
return 0;
}
int cleanup_module(void)
{
printk(KERN_ALERT "\nGoodbye kernel\n");
}



but still not getting the solution it will be so graceful if you can help me out

thanks in advance.

sometimes it gives this error during insertion.I am not very sure how it can be fixed but yes,you can do one thing--compile your kernel with modversioning option OFF.just do make menuconfig,there you go to "Loadable module support" option ,select it and in that you will find "set version info on all module symbols",make it N and compile the kernel.
then there is no need for if CONFIG_MODVERSIONS code.
no need for version.h either.
also add #define MODULE in your code.
hope it will work