i am working on fedora core 8 installed as a guest OS on a vmware server

i am trying to generate a sample kernel object file called a .ko file from a .c file to print "hello world".
i have written a Makefile to compile the .c file and generate a .ko file.
both the files are as follows:

------------------------------------------------------
//hello.c

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


static int __init hello_init(void)
{
printk(KERN_ALERT "hello world!!!!!!\n");
return 0;
}

static void __exit hello_exit(void)
{
printk(KERN_ALERT "good bye!!!!!!\n");
}

module_init(hello_init);
module_exit(hello_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("test module");
MODULE_AUTHOR("HASH123");

-----------------------------------------------------------

-------------------------------------------------------------
//Makefile

obj-m := hello.o
KDIR := /lib/modules/$(shell uname -r)/build
PWD := $(shell pwd)
default:
$(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules

------------------------------------------------------------


now when i type the "make" command i get the following error:


make -C /lib/modules/2.6.23.1-42.fc8/build SUBDIRS=root/hash123/test modules
make: *** /lib/modules/2.6.23.1-42.fc8/build: no such file or directory. Stop.
make: *** [default] Error 2


can anybody tell me what is the problem and how to solve the problem?

Does the directory exist?

it exists as a link at the path /lib/modules/2.6.23.1-42.fc8/

it is a link to the directory /usr/src/kernels/2.6.23.1-42.fc8-i686/

but i checked that my /usr/src/ directory is empty.

so now what do i do?

You have to install the kernel sources. Package is kernel-devel-2.6.23.1-42.fc8.i686.

where do i get the package from and how do i install it?
also at what path should the package be kept to install it?

I asked Google: fedora core 8 packages install
The first hit seems useful:

http://www.fedorafaq.org/

You can either use the graphical interface or the command line. Using the graphical interface is as simple as selcting "Add/Remove Software" from the "System -> Administration" menu. Using the command line is as simple as running the following command from a terminal:
Don't bother about the installation path: it is hardcoded in the package itself and all the files will be installed in the standard locations. Obviuosly - as you expect - the kernel source will be installed under /usr/src.

i have successfully installed the required rpm and
now when type make at the commandline it gives the following error:

[root@dlhgn47dhcp157 test]# make
make -C /usr/src/kernels/2.6.23.1-42.fc8-i686/ SUBDIRS=/root/hash123/test modules
/usr/src/kernels/2.6.23.1-42.fc8-i686/scripts/gcc-version.sh: line 16: gcc: command not found
/usr/src/kernels/2.6.23.1-42.fc8-i686/scripts/gcc-version.sh: line 17: gcc: command not found
make[1]: gcc: Command not found
make[1]: Entering directory `/usr/src/kernels/2.6.23.1-42.fc8-i686'
CC [M] /root/hash123/test/hello.o
/bin/sh: gcc: command not found
make[2]: *** [/root/hash123/test/hello.o] Error 127
make[1]: *** [_module_/root/hash123/test] Error 2
make[1]: Leaving directory `/usr/src/kernels/2.6.23.1-42.fc8-i686'
make: *** [default] Error 2

You could try making the symbolic links manually with 'ln -s /usr/src/kernels/2.6.23.1-42.fc8-i686/ /lib/modules/2.6.23.1-42.fc8/build; ln -s /usr/src/kernels/2.6.23.1-42.fc8-i686/ /lib/modules/2.6.23.1-42.fc8/source' (but they *should* be there) or change your KDIR to read "KDIR := /usr/src/kernels/2.6.23.1-42.fc8-i686".

the links already exist.It is not the problem with the links

the problem exists somewhere else

Do you have no compiler installed?

Right. No compiler installed.

is there any other way to install the gcc compiler without using yum ?

Why would you want to do that? (rhetorical question - sorry)
1.) you can install the .rpm directly - but is does have dependencies _you_ need to solve then
2.) you build your own compiler...mmh ...no - you need a compiler for this
You could use yum to install it temporarily - build your own - and deinstall the one installed by yum

Other than that - have a look at the documentation for LFS - maybe you find a way there.
http://www.linuxfromscratch.org/lfs/view/stable/

Use the graphical interface (as suggested above). From the Gnome Menu -> System -> Administration -> Add/Remove Software. yum from command line is the quicker method, anyway.