address_families(7) - man - phpman

ADDRESS_FAMILIES(7)                   Linux Programmer's Manual                  ADDRESS_FAMILIES(7)



NAME
       address_families - socket address families (domains)

SYNOPSIS
       #include <sys/types.h>          /* See NOTES */
       #include <sys/socket.h>

       int socket(int domain, int type, int protocol);

DESCRIPTION
       The  domain argument of the socket(2) specifies a communication domain; this selects the pro‐
       tocol  family  which  will  be  used  for  communication.   These  families  are  defined  in
       <sys/socket.h>.  The formats currently understood by the Linux kernel include:

       AF_UNIX, AF_LOCAL
              Local communication For further information, see unix(7).

       AF_INET
              IPv4 Internet protocols.  For further information, see ip(7).

       AF_AX25
              Amateur radio AX.25 protocol.  For further information, see ax25(4).

       AF_IPX IPX - Novell protocols.

       AF_APPLETALK
              AppleTalk For further information, see ddp(7).

       AF_NETROM
              AX.25 packet layer protocol.  For further information, see netrom(4), The Packet Radio
              Protocols and Linux ⟨https://www.tldp.org/HOWTO/AX25-HOWTO/x61.html⟩  and  the  AX.25,
              NET/ROM,  and ROSE network programming chapters of the Linux Amateur Radio AX.25 HOWTO
              ⟨https://www.tldp.org/HOWTO/AX25-HOWTO/x2107.html⟩.

       AF_BRIDGE
              Can't be used for creating sockets; mostly used for bridge links in rtnetlink(7)  pro‐
              tocol commands.

       AF_ATMPVC
              Access to raw ATM Permanent Virtual Circuits (PVCs).  For further information, see the
              ATM on Linux HOWTO ⟨https://www.tldp.org/HOWTO/text/ATM-Linux-HOWTO⟩.

       AF_X25 ITU-T X.25 / ISO-8208 protocol.  For further information, see x25(7).

       AF_INET6
              IPv6 Internet protocols.  For further information, see ipv6(7).

       AF_ROSE
              RATS (Radio Amateur Telecommunications Society) Open Systems environment (ROSE)  AX.25
              packet  layer  protocol.   For  further  information,  see  the  resources  listed for
              AF_NETROM.

       AF_DECnet
              DECet protocol sockets.  See Documentation/networking/decnet.txt in the  Linux  kernel
              source tree for details.

       AF_NETBEUI
              Reserved for "802.2LLC project"; never used.

       AF_SECURITY
              This was a short-lived (between Linux 2.1.30 and 2.1.99pre2) protocol family for fire‐
              wall upcalls.

       AF_KEY Key management protocol, originally  developed  for  usage  with  IPsec  (since  Linux
              2.1.38).   This  has  no relation to keyctl(2) and the in-kernel key storage facility.
              See     RFC     2367     PF_KEY      Key      Management      API,      Version      2
              ⟨https://tools.ietf.org/html/rfc2367⟩ for details.

       AF_NETLINK
              Kernel user interface device For further information, see netlink(7).

       AF_PACKET
              Low-level packet interface.  For further information, see packet(7).

       AF_ECONET
              Acorn   Econet  protocol  (removed  in  Linux  3.5).   See  the  Econet  documentation
              ⟨http://www.8bs.com/othrdnld/manuals/econet.shtml⟩ for details.

       AF_ATMSVC
              Access  to  ATM  Switched  Virtual  Circuits  (SVCs)  See  the  ATM  on  Linux   HOWTO
              ⟨https://www.tldp.org/HOWTO/text/ATM-Linux-HOWTO⟩ for details.

       AF_RDS Reliable  Datagram  Sockets (RDS) protocol (since Linux 2.6.30).  RDS over RDMA has no
              relation to AF_SMC or AF_XDP.  For further information see  rds(7),  rds-rdma(7),  and
              Documentation/networking/rds.txt in the Linux kernel source tree.

       AF_IRDA
              Socket  interface  over  IrDA (moved to staging in Linux 4.14, removed in Linux 4.17).
              For further information see irda(7).

       AF_PPPOX
              Generic PPP transport layer, for setting up L2 tunnels (L2TP and PPPoE).  See Documen‐
              tation/networking/l2tp.txt in the Linux kernel source tree for details.

       AF_WANPIPE
              Legacy  protocol for wide area network (WAN) connectivity that was used by Sangoma WAN
              cards (called "WANPIPE"); removed in Linux 2.6.21.

       AF_LLC Logical link control (IEEE 802.2 LLC) protocol, upper  part  of  data  link  layer  of
              ISO/OSI  networking  protocol  stack  (since Linux 2.4); has no relation to AF_PACKET.
              See chapter 13.5.3. Logical Link  Control  in  Understanding  Linux  Kernel  Internals
              (O'Reilly  Media,  2006) and IEEE Standards for Local Area Networks: Logical Link Con‐
              trol (The Institute of Electronics and Electronics  Engineers,  Inc.,  New  York,  New
              York,     1985)     for     details.      See     also     some    historical    notes
              ⟨https://wiki.linuxfoundation.org/networking/llc⟩ regarding its development.

       AF_IB  InfiniBand native addressing (since Linux 3.11).

       AF_MPLS
              Multiprotocol Label Switching (since Linux 4.1);  mostly  used  for  configuring  MPLS
              routing via netlink(7), as it doesn't expose ability to create sockets to user space.

       AF_CAN Controller  Area Network automotive bus protocol (since Linux 2.6.25).  See Documenta‐
              tion/networking/can.rst in the Linux kernel source tree for details.

       AF_TIPC
              TIPC, "cluster domain sockets" protocol (since Linux 2.6.16).  See  TIPC  Programmer's
              Guide     ⟨http://tipc.io/programming.html⟩     and     the    protocol    description
              ⟨http://tipc.io/protocol.html⟩ for details.

       AF_BLUETOOTH
              Bluetooth low-level socket protocol (since Linux 3.11).  See Bluetooth Management  API
              overview    ⟨https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/doc/mgmt-api.txt⟩
              and    An    Introduction    to    Bluetooth    Programming    by     Albert     Huang
              ⟨https://people.csail.mit.edu/albert/bluez-intro/⟩ for details.

       AF_IUCV
              IUCV (inter-user communication vehicle) z/VM protocol for hypervisor-guest interaction
              (since Linux 2.6.21); has no relation to AF_VSOCK  and/or  AF_SMC  See  IUCV  protocol
              overview                  ⟨https://www.ibm.com/support/knowledgecenter/en/SSB27U_6.4.0
              /com.ibm.zvm.v640.hcpb4/iucv.htm⟩ for details.

       AF_RXRPC
              Rx, Andrew File System remote procedure call protocol (since Linux 2.6.22).  See Docu‐
              mentation/networking/rxrpc.txt in the Linux kernel source tree for details.

       AF_ISDN
              New "modular ISDN" driver interface protocol (since Linux 2.6.27).  See the mISDN wiki
              ⟨http://www.misdn.eu/wiki/Main_Page/⟩ for details.

       AF_PHONET
              Nokia cellular modem IPC/RPC interface (since Linux 2.6.31).   See  Documentation/net‐
              working/phonet.txt in the Linux kernel source tree for details.

       AF_IEEE802154
              IEEE  802.15.4  WPAN (wireless personal area network) raw packet protocol (since Linux
              2.6.31).  See Documentation/networking/ieee802154.txt in the Linux kernel source  tree
              for details.

       AF_CAIF
              Ericsson's Communication CPU to Application CPU interface (CAIF) protocol (since Linux
              2.6.36).  See Documentation/networking/caif/Linux-CAIF.txt in the Linux kernel  source
              tree for details.

       AF_ALG Interface   to   kernel   crypto   API   (since   Linux   2.6.38).    See   Documenta‐
              tion/crypto/userspace-if.rst in the Linux kernel source tree for details.

       AF_VSOCK
              VMWare VSockets protocol for hypervisor-guest interaction (since Linux  3.9);  has  no
              relation to AF_IUCV and AF_SMC.  For further information, see vsock(7).

       AF_KCM KCM  (kernel  connection  multiplexer)  interface  (since  Linux 4.6).  See Documenta‐
              tion/networking/kcm.txt in the Linux kernel source tree for details.

       AF_QIPCRTR
              Qualcomm IPC router interface protocol (since Linux 4.7).

       AF_SMC SMC-R (shared memory communications over RDMA) protocol (since Linux 4.11), and  SMC-D
              (shared  memory  communications,  direct  memory  access) protocol for intra-node z/VM
              quest interaction (since Linux 4.19); has no relation to AF_RDS, AF_IUCV or  AF_VSOCK.
              See   RFC   7609  IBM's  Shared  Memory  Communications  over  RDMA  (SMC-R)  Protocol
              ⟨https://tools.ietf.org/html/rfc7609⟩  for  details  regarding   SMC-R.    See   SMC-D
              Reference     Information     ⟨https://www-01.ibm.com/software/network/commserver/SMC-
              D/index.html⟩ for details regarding SMC-D.

       AF_XDP XDP (express data path) interface  (since  Linux  4.18).   See  Documentation/network‐
              ing/af_xdp.rst in the Linux kernel source tree for details.

SEE ALSO
       socket(2), socket(7)

COLOPHON
       This  page  is  part  of  release  5.10 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of this page, can be  found
       at https://www.kernel.org/doc/man-pages/.



Linux                                        2018-10-16                          ADDRESS_FAMILIES(7)