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GETPEERNAME(2)              BSD System Calls Manual             GETPEERNAME(2)

     getpeername -- get name of connected peer

     #include <sys/socket.h>

     getpeername(int socket, struct sockaddr *restrict address,
         socklen_t *restrict address_len);

     Getpeername() returns the name of the peer connected to socket socket.
     The address_len 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).  The name is truncated if the buffer provided
     is too small.

     The getpeername() function returns the value 0 if successful; otherwise
     the value -1 is returned and the global variable errno is set to indicate
     the error.

     The call succeeds unless:

     [EBADF]            The argument socket is not a valid descriptor.

     [EFAULT]           The address parameter points to memory not in a valid
                        part of the process address space.

     [EINVAL]           socket has been shut down.

     [ENOBUFS]          Insufficient resources were available in the system to
                        perform the operation.

     [ENOTCONN]         Either the socket is not connected or it has not had
                        the peer pre-specified.

     [ENOTSOCK]         The argument socket refers to something other than a
                        socket (e.g., a file).

     [EOPNOTSUPP]       getpeername() is not supported for the protocol in use
                        by socket.

     accept(2), bind(2), getsockname(2), socket(2)

     The getpeername() function call appeared in 4.2BSD.

4.2 Berkeley Distribution        June 4, 1993        4.2 Berkeley Distribution