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.\"     @(#)getpeername.2	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: head/lib/libc/sys/getpeername.2 243439 2012-11-23 10:14:54Z kevlo $
.\"
.Dd June 4, 1993
.Dt GETPEERNAME 2
.Os
.Sh NAME
.Nm getpeername
.Nd get name of connected peer
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/types.h
.In sys/socket.h
.Ft int
.Fn getpeername "int s" "struct sockaddr * restrict name" "socklen_t * restrict namelen"
.Sh DESCRIPTION
The
.Fn getpeername
system call
returns the name of the peer connected to
socket
.Fa s .
The
.Fa namelen
argument should be initialized to indicate
the amount of space pointed to by
.Fa 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.
.Sh RETURN VALUES
.Rv -std getpeername
.Sh ERRORS
The call succeeds unless:
.Bl -tag -width Er
.It Bq Er EBADF
The argument
.Fa s
is not a valid descriptor.
.It Bq Er ECONNRESET
The connection has been reset by the peer.
.It Bq Er EINVAL
The value of the
.Fa namelen
argument is not valid.
.It Bq Er ENOTSOCK
The argument
.Fa s
is a file, not a socket.
.It Bq Er ENOTCONN
The socket is not connected.
.It Bq Er ENOBUFS
Insufficient resources were available in the system
to perform the operation.
.It Bq Er EFAULT
The
.Fa name
argument points to memory not in a valid part of the
process address space.
.El
.Sh SEE ALSO
.Xr accept 2 ,
.Xr bind 2 ,
.Xr getsockname 2 ,
.Xr socket 2
.Sh HISTORY
The
.Fn getpeername
system call appeared in
.Bx 4.2 .