man2/getsockname.2

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.\"     @(#)getsockname.2	6.4 (Berkeley) 3/10/91
.\"
.\" Modified Sat Jul 24 16:30:29 1993 by Rik Faith <faith@cs.unc.edu>
.\" Modified Tue Oct 22 00:22:35 EDT 1996 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified Sun Mar 28 21:26:46 1999 by Andries Brouwer <aeb@cwi.nl>
.\"
.TH GETSOCKNAME 2 2021-03-22 "Linux" "Linux Programmer's Manual"
.SH NAME
getsockname \- get socket name
.SH SYNOPSIS
.nf
.B #include <sys/socket.h>
.PP
.BI "int getsockname(int " sockfd ", struct sockaddr *restrict " addr ,
.BI "                socklen_t *restrict " addrlen );
.fi
.SH DESCRIPTION
.BR getsockname ()
returns the current address to which the socket
.I sockfd
is bound, in the buffer pointed to by
.IR addr .
The
.I addrlen
argument should be initialized to indicate
the amount of space (in bytes) pointed to by
.IR addr .
On return it contains the actual size of the socket address.
.PP
The returned address is truncated if the buffer provided is too small;
in this case,
.I addrlen
will return a value greater than was supplied to the call.
.SH RETURN VALUE
On success, zero is returned.
On error, \-1 is returned, and
.I errno
is set to indicate the error.
.SH ERRORS
.TP
.B EBADF
The argument
.I sockfd
is not a valid file descriptor.
.TP
.B EFAULT
The
.I addr
argument points to memory not in a valid part of the
process address space.
.TP
.B EINVAL
.I addrlen
is invalid (e.g., is negative).
.TP
.B ENOBUFS
Insufficient resources were available in the system
to perform the operation.
.TP
.B ENOTSOCK
The file descriptor
.I sockfd
does not refer to a socket.
.SH CONFORMING TO
POSIX.1-2001, POSIX.1-2008, SVr4, 4.4BSD
.RB ( getsockname ()
first appeared in 4.2BSD).
.\" SVr4 documents additional ENOMEM
.\" and ENOSR error codes.
.SH NOTES
For background on the
.I socklen_t
type, see
.BR accept (2).
.SH SEE ALSO
.BR bind (2),
.BR socket (2),
.BR getifaddrs (3),
.BR ip (7),
.BR socket (7),
.BR unix (7)