HP-UX Reference (11i v2 03/08) - 2 System Calls (vol 5)

g
getpeername(2) getpeername(2)
NAME
getpeername - get address of connected peer
SYNOPSIS
#include <sys/socket.h>
AF_CCITT only:
#include <x25/x25addrstr.h>
int getpeername(int s, void *addr, int *addrlen);
_XOPEN_SOURCE_EXTENDED only (UNIX 98)
int getpeername(int s, struct sockaddr *addr, socklen_t *addrlen);
Obsolescent _XOPEN_SOURCE_EXTENDED only (UNIX 95)
int getpeername(int s, struct sockaddr *addr, size_t *addrlen);
DESCRIPTION
getpeername()
returns the address of the peer socket connected to the socket indicated by s, where s
is a socket descriptor. addr points to a socket address structure in which this address is returned.
addrlen points to a variable that should be initialized to indicate the size of the address structure. On
return, the variable contains the actual size of the address returned (in bytes). If addr does not point to
enough space to contain the whole address of the peer, only the first addrlen bytes of the address are
returned.
AF_CCITT only:
The addr struct contains the X.25 addressing information of the remote peer socket connected to socket s.
However, the
x25ifname[] field of the addr struct contains the name of the local X.25 interface
through which the call arrived.
RETURN VALUE
Upon successful completion,
getpeername() returns 0; otherwise it returns −1 and sets
errno to
indicate the error.
ERRORS
getpeername() fails if any of the following conditions are encountered:
[EBADF] s is not a valid file descriptor.
[ENOTSOCK] s is a valid file descriptor, but it is not a socket.
[ENOTCONN] The socket is not connected.
[ENOBUFS] No buffer space is available to perform the operation.
[EFAULT] addr or addrlen are not valid pointers.
[EINVAL] The socket has been shut down.
OBSOLESCENCE
Currently, the
socklen_t and size_t types are the same size. This is compatible with both the UNIX
95 and UNIX 98 profiles. However, in a future release, socklen_t might be a different size. In that
case, passing a size_t pointer will evoke compile-time warnings, which must be corrected in order for
the application to behave correctly. Applications that use socklen_t now, where appropriate, will
avoid such migration problems. On the other hand, applications that need to be portable to the UNIX 95
profile should follow the X/Open specification (see xopen_networking(7)).
FUTURE DIRECTION
Currently, the default behavior is the HP-UX BSD Sockets; however, it might be changed to X/Open
Sockets in a future release. At that time, any HP-UX BSD Sockets behavior that is incompatible with
X/Open Sockets might be obsoleted. Applications that conform to the X/Open specification now will
avoid migration problems (see xopen_networking(7)).
AUTHOR
getpeername() was developed by HP and the University of California, Berkeley.
HP-UX 11i Version 2: August 2003 − 1 − Hewlett-Packard Company Section 2−−101