cc [ flag ... ] file ... –lsocket –lnsl [ library ... ] #include <sys/socket.h> int getpeername(int s, struct sockaddr *name, socklen_t *namelen);
getpeername() returns the name of the peer connected to socket s. The int pointed to by 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), prior to any truncation. The name is truncated if the buffer provided is too small.
If successful, getpeername() returns 0; otherwise it returns −1 and sets errno to indicate the error.
The call succeeds unless:
The argument s is not a valid descriptor.
There was insufficient user memory for the operation to complete.
There were insufficient STREAMS resources available for the operation to complete.
The socket is not connected.
The argument s is not a socket.
See attributes(5) for descriptions of the following attributes: