Patch files

During our work on linux environment, we might often come across the situation of updating the source files we work on using patch files. That is, the need for updating the source files for changes.

The patch files have the differences between the source (say X) that is to be updated and the updated version of that source (X).

So how to create a patch file? or how to patch up a source with the provided patch file? These are very well explained under Tools and Techniques.

Installing windows - Could not load CD/DVD drive

"Hey, I have a problem with installing windows 7 on my laptop. Could you please help me out." said my colleague. He got the laptop from US. It was gifted to him by his elder brother who was there for an on-site assignment. The laptop is a make of HP (Pavilion dv4-2173nr) and had windows 7 installed. Wishing to have a linux distribution on the laptop he lost his windows 7 installation.

Now on trying to install the windows 7 he encounters the following error:

Windows Install could not load the CD/DVD drive that contains the installation media.  Please provide the necessary drive or controller device drivers provided by your manufacturer.

The error message doesn't help at all. The actual problem is that the windows 7 installation media doesn't have a driver for the hard disk available with the laptop.

Searched and downloaded the driver for the hard disk (of Pavilion dv4-2173nr) from the HP site.

Loaded the driver into USB memory stick and used it during the installation. The installation was successful.