getpeername - get name of connected peer
#include <sys/socket.h>
int getpeername(int s, struct sockaddr *name, socklen_t *namelen);
getpeername(2) returns the name of the peer connected to socket s. 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). The name is truncated if the buffer provided is too small.
On success, zero is returned. On error, -1 is returned, and errno is set appropriately.
SVr4, 4.4BSD (the getpeername function call first appeared in 4.2BSD).
The third argument of getpeername is in reality an `int ' (and this is what BSD 4. and libc4 and libc5 have). Some POSIX confusion resulted in the present socklen_t. The draft standard has not been adopted yet, but glibc2 already follows it and also has socklen_t. See also accept(2).
3 pages link to getpeername(2):