GETPEERNAME Section: Linux Programmer's Manual (2) Updated: 30 July 2025 Index   NAME getpeername - get name of connected peer   SYNOPSIS #include <sys/socket.h> int getpeername(int s, struct sockaddr *name, socklen_t *namelen);   DESCRIPTION Getpeername 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.   RETURN VALUE On success, zero is returned. On error, -1 is returned, and errno is set appropriately.   ERRORS EBADF The argument s is not a valid descriptor. 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 parameter points to memory not in a valid part of the process address space.   CONFORMING TO SVr4, 4.4BSD (the getpeername function call first appeared in 4.2BSD).   NOTE 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   SEE ALSO   Index NAME SYNOPSIS DESCRIPTION RETURN VALUE ERRORS CONFORMING TO NOTE SEE ALSO This document was created by using the manual pages. Time: 11:56:06 GMT, March 24, 2025