I am student from CS background and I have Operating Systems in my upcoming semester. A simple search around the internet revealed that that Operating System Concepts by Silberschatz and Galvin is one of the best ones to follow.
Now the above text is probably in its 10th edition currently. Now I won't be able to afford a physical copy of the latest edition, so I was looking around for few cheap used copies and found abundance of 5th edition and few 6th edition texts.
Are these two older editions still recommended? If I only want to build my basics and I have no prior knowledge of the above subject. Any help shall be greatly appreciated...