freebsd man page for getpeername

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

NAME
     getpeername -- get name of connected peer

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/types.h>
     #include <sys/socket.h>

     int
     getpeername(int s, struct sockaddr * restrict name, socklen_t * restrict namelen);

DESCRIPTION
     The getpeername() system call returns the name of the peer connected to socket s.	The namelen argument 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.

RETURN VALUES
     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.

ERRORS
     The call succeeds unless:

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

     [ECONNRESET]	The connection has been reset by the peer.

     [EINVAL]		The value of the namelen argument is not valid.

     [ENOTSOCK] 	The argument s is a file, not a socket.

     [ENOTCONN] 	The socket is not connected.

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

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

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

HISTORY
     The getpeername() system call appeared in 4.2BSD.

BSD
								   June 4, 1993 							       BSD