This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
getsockname — get the socket name
int getsockname(int socket, struct sockaddr *restrict address,
socklen_t *restrict address_len);
The getsockname() function shall retrieve the locally-bound name of the
specified socket, store this address in the sockaddr structure pointed
to by the address argument, and store the length of this address in the
object pointed to by the address_len argument.
The address_len argument points to a socklen_t
object which on input specifies the length of the supplied sockaddr
structure, and on output specifies the length of the stored address. If the
actual length of the address is greater than the length of the supplied
sockaddr structure, the stored address shall be truncated.
If the socket has not been bound to a local name, the value stored
in the object pointed to by address is unspecified.
Upon successful completion, 0 shall be returned, the address argument
shall point to the address of the socket, and the address_len argument
shall point to the length of the address. Otherwise, -1 shall be returned and
errno set to indicate the error.
The getsockname() function shall fail if:
- The socket argument is not a valid file descriptor.
- The socket argument does not refer to a socket.
- The operation is not supported for this socket's protocol.
The getsockname() function may fail if:
- The socket has been shut down.
- Insufficient resources were available in the system to complete the
The following sections are informative.
accept(), bind(), getpeername(),
The Base Definitions volume of POSIX.1‐2017,
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1-2017, Standard for Information Technology -- Portable Operating
System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018
Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html .
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