getsockname(2)getsockname(2)NAMEgetsockname - Get the socket name
SYNOPSIS
#include <sys/socket.h>
int getsockname(
int socket,
struct sockaddr *address,
socklen_t *address_len );
[XNS4.0] The definition of the getsockname() function in XNS4.0 uses a
size_t data type instead of a socklen_t data type as specified in
XNS5.0 (the previous definition).
[Tru64 UNIX] The following definition of the getsockname() function
does not conform to current standards and is supported only for back‐
ward compatibility (see standards(5)): #include <sys/socket.h>
int getsockname(
int socket,
struct sockaddr *address,
int *address_len );
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
getsockname(): XNS4.0, XNS5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
PARAMETERS
Specifies the socket file descriptor for which the local address is
needed. Points to a sockaddr structure, the format of which is deter‐
mined by the domain and by the behavior requested for the socket. The
sockaddr structure is an overlay for a sockaddr_in, sockaddr_un, sock‐
addr_in6, or sockaddr_storage structure, depending on which of the sup‐
ported address families is active.
[Tru64 UNIX] If the compile-time option _SOCKADDR_LEN is
defined before the sys/socket.h header file is included, the
sockaddr structure takes 4.4BSD behavior, with a field for spec‐
ifying the length of the socket address. Otherwise, the default
4.3BSD sockaddr structure is used, with the length of the socket
address assumed to be 14 bytes or less.
If _SOCKADDR_LEN is defined, the 4.3BSD sockaddr structure is
defined with the name osockaddr. Specifies the length of the
sockaddr structure pointed to by the address parameter.
DESCRIPTION
The getsockname() function retrieves the locally bound address of the
specified socket.
If the actual length of the address is greater than the length of the
sockaddr structure, the address is truncated.
If the socket is not bound to a local name, the value pointed to by
address is unspecified.
A process created by another process can inherit open sockets. To use
the inherited sockets, the created process may need to identify its
address. The getsockname() function allows a process to retrieve the
local address bound to the specified socket.
A process can use the getpeername() function to determine the address
of a destination socket in a socket connection.
NOTES
[Tru64 UNIX] When compiled in the X/Open UNIX environment or the
POSIX.1g socket environment, calls to the getsockname() function are
internally renamed by prepending _E to the function name. When you are
debugging a module that includes the getsockname() function and for
which _XOPEN_SOURCE_EXTENDED or _POSIX_PII_SOCKET has been defined, use
_Egetsockname to refer to the getsockname() call. See standards(5) for
further information.
RETURN VALUES
Upon successful completion, a value of 0 (zero) is returned, and the
address_len parameter points to the size of the socket address. Other‐
wise, a value of -1 is returned and errno is set to indicate the error.
ERRORS
If the getsockname() function fails, errno may be set to one of the
following values: The socket parameter is not valid. The address or
address_len parameter is not in a readable or writable part of the user
address space. The socket is shut down. Insufficient resources are
available in the system to complete the call. The available STREAMS
resources were insufficient for the operation to complete. The socket
parameter refers to a file, not a socket. The operation is not sup‐
ported for this socket's protocol.
SEE ALSO
Functions: accept(2), bind(2), getpeername(2), socket(2).
Standards: standards(5).
Network Programmer's Guide
getsockname(2)