title: /lib/modules/<version>/build/ not existent
body: <p>I am trying to write a very basic "Hello World" device driver example which is taught in any device driver implementation introductory course. My makefile is as follows:</p>
  
  <pre><code>obj-m := hello.o
  
  KDIR := /lib/modules/$(shell uname -r)/bulid
  
  PWD := $(shell pwd)
  
  all:
   make -C $(KDIR) M=$(PWD) modules
  </code></pre>
  
  <p>When I am using the make command, it is showing that /lib/modules/version_no/build/ is not existent. So I entered the directory /lib/modules/version_no and found that there is one directory build but if I use the ls command, it is printed in red colour, which means that the directory is deprecated. It contains one link to ../../../usr/src/version_no, but to my surprise, the version number in that link and the name of the actual folder in /usr/src/ are not same. Can anyone point out what is the issue? I am using centos 6.1.</p>