Getting info about network devices

[Krishnendu Sadhukhan]

Hi,

	I want to programmatically extract the list of network devices currently existing in the system. More specifically, I want to know the following:

	i) the list of all interfaces configured by the system at boot time
	ii) the list of all available interfaces at a particular moment
	iii) the list of all logical interfaces at a particular moment.

	I was looking at /proc/net/dev, but it seems it does not give the complete information, especially the information on the logical interfaces.

	What is the best place in the system to look for this information ?

Thanks,
Krish