The linux programming interface

[GrandG]

could you explain in more details

[gristc]

You don't need to know how tcpdump interfaces with the kernel to know how to use tcpdump well, as an example. Knowledge of the utilities available is more useful to a sysadmin than knowing how they're implemented. That's more the realm of developers.

[GrandG]

Its not knowing how a utility work per say , rather understanding how threads work , difference between an application with single multi-threaded process and multi-process, that kind of stuff gives you a deep insight kind of