What Linux library supports sockets, ioctl calls, tuntap, etc...?

Question

What is the name of the runtime library which implements Linux network interfaces, like sockets, tuntaps, netlink, etc...? For example when I create an UDP socket and make an ioctl call to fetch network interface info, which library actually implements that call? What are the corresponding *.so files on most linux dstirbutions?

Answer 1

These are c library calls, and as such are in the libc library.

Answer 2

They're not all in libc, although many are. Tun/Tap has its own library, so does netlink. Basic socket operations are in libc.

Answer 3

The C library exports the functions, but they are just wrappers for sys calls. The actual socket functions themselves are implemented inside the kernel.

So pull it to pieces starting with sys_socket - it's not that difficult, and LXR makes it easy.