getsockname - get socket name
int getsockname(int s , struct sockaddr * name , int *
Getsockname returns the current name for the specified
socket. The namelen parameter should be initialized to
indicate the amount of space pointed to by name. On return
it contains the actual size of the name returned (in bytes).
On success, zero is returned. On error, -1 is returned, and
errno is set appropriately. A 0 is returned if the call
succeeds, -1 if it fails.
EBADF The argument s is not a valid descriptor.
The argument s is a file, not a socket.
ENOBUFS Insufficient resources were available in the system
to perform the operation.
EFAULT The name parameter points to memory not in a valid
part of the process address space.
SVr4, 4.4BSD (the getsockname function call appeared in
4.2BSD). SVr4 documents additional ENOMEM and ENOSR error