--- name: "ost_UDPSocket" section: "3" platform: "linux" package: "libcommoncpp2-doc" version: "1.8.1-10" release: "Debian 11 (Bullseye)" platforms: ["linux"] url: "https://new.carta.tech/ost_UDPSocket" --- # ost\_UDPSocket(3) UDP sockets implement the TCP SOCK\_DGRAM UDP protocol. ## NAME ost::UDPSocket - UDP sockets implement the TCP SOCK\_DGRAM UDP protocol. ## SYNOPSIS `#include ` Inherits **ost::Socket**. Inherited by **ost::UDPBroadcast**, **ost::UDPReceive**` [protected]`, and **ost::UDPTransmit**` [protected]`. ### Public Member Functions **UDPSocket** (**Family** **family**=**IPV4**)\ Create an unbound UDP socket, mostly for internal use. **UDPSocket** (const char \*name, **Family** **family**=**IPV4**)\ Create a UDP socket bound by a service name. **UDPSocket** (const **IPV4Address** &bind, **tpport\_t** port)\ Create a UDP socket and bind it to a specific interface and port address so that other UDP sockets on remote machines (or the same host) may find and send UDP messages to it. **UDPSocket** (const **IPV6Address** &bind, **tpport\_t** port)\ virtual **~UDPSocket** ()\ Destroy a UDP socket as a socket. **Error** **setLoopback** (bool enable)\ Set the loopback. **Error** **setMulticast** (bool enable)\ Set the multicast. **Error** **setTimeToLive** (char **ttl**)\ Set time to live. void **setPeer** (const **IPV4Host** &host, **tpport\_t** port)\ set the peer address to send message packets to. void **connect** (const **IPV4Host** &host, **tpport\_t** port)\ void **setPeer** (const **IPV6Host** &host, **tpport\_t** port)\ void **connect** (const **IPV6Host** &host, **tpport\_t** port)\ **Socket::Error** **getInterfaceIndex** (const char \*ethX, int &InterfaceIndex)\ get the interface index for a named network device **Socket::Error** **join** (const **IPV4Multicast** &ia, int InterfaceIndex)\ join a multicast group on a particular interface ssize\_t **send** (const void \*buf, size\_t len)\ Send a message packet to a peer host. ssize\_t **receive** (void \*buf, size\_t len, bool reply=false)\ Receive a message from any host. **IPV4Host** **getIPV4Peer** (**tpport\_t** \*port=NULL) const\ Examine address of sender of next waiting packet. **IPV4Host** **getPeer** (**tpport\_t** \*port=NULL) const\ **IPV6Host** **getIPV6Peer** (**tpport\_t** \*port=NULL) const\ ssize\_t **peek** (void \*buf, size\_t len)\ Examine contents of next waiting packet. void **setPeer** (const char \*service)\ Associate socket with a named connection. void **connect** (const char \*service)\ **Error** **disconnect** (void)\ Disassociate this socket from any host connection. ### Protected Attributes union {\ struct sockaddr\_in6 **ipv6**\ struct sockaddr\_in **ipv4**\ } **peer**\ **Family** **family**\ ### Additional Inherited Members ## Detailed Description UDP sockets implement the TCP SOCK\_DGRAM UDP protocol. They can be used to pass unverified messages between hosts, or to broadcast a specific message to an entire subnet. Please note that Streaming of realtime data commonly use **UDPDuplex** related classes rather than **UDPSocket**. In addition to connected TCP sessions, Common C++ supports UDP sockets and these also cover a range of functionality. Like a **TCPSocket**, A **UDPSocket** can be created bound to a specific network interface and/or port address, though this is not required. UDP sockets also are usually either connected or otherwise 'associated' with a specific 'peer' UDP socket. Since UDP sockets operate through discreet packets, there are no streaming operators used with UDP sockets. In addition to the UDP 'socket' class, there is a 'UDPBroadcast' class. The **UDPBroadcast** is a socket that is set to send messages to a subnet as a whole rather than to an individual peer socket that it may be associated with. UDP sockets are often used for building 'realtime' media streaming protocols and full duplex messaging services. When used in this manner, typically a pair of UDP sockets are used together; one socket is used to send and the other to receive data with an associated pair of UDP sockets on a 'peer' host. This concept is represented through the Common C++ **UDPDuplex** object, which is a pair of sockets that communicate with another **UDPDuplex** pair. **Author** David Sugar dyfet@ostel.com Unreliable Datagram Protocol sockets. ## Constructor & Destructor Documentation ### ost::UDPSocket::UDPSocket (Family family = IPV4) Create an unbound UDP socket, mostly for internal use. ### ost::UDPSocket::UDPSocket (const char \* name, Family family = IPV4) Create a UDP socket bound by a service name. ### ost::UDPSocket::UDPSocket (const IPV4Address & bind, tpport\_t port) Create a UDP socket and bind it to a specific interface and port address so that other UDP sockets on remote machines (or the same host) may find and send UDP messages to it. On failure to bind, an exception is thrown. **Parameters** *bind* address to bind this socket to. \ *port* number to bind this socket to. ### ost::UDPSocket::UDPSocket (const IPV6Address & bind, tpport\_t port) ### virtual ost::UDPSocket::~UDPSocket ()` [virtual]` Destroy a UDP socket as a socket. ## Member Function Documentation ### void ost::UDPSocket::connect (const char \* service) ### void ost::UDPSocket::connect (const IPV4Host & host, tpport\_t port) ### void ost::UDPSocket::connect (const IPV6Host & host, tpport\_t port) ### Error ost::UDPSocket::disconnect (void) Disassociate this socket from any host connection. No data should be read or written until a connection is established. ### Socket::Error ost::UDPSocket::getInterfaceIndex (const char \* ethX, int & InterfaceIndex) get the interface index for a named network device **Parameters** *ethX* is device name, like 'eth0' or 'eth1' \ *InterfaceIndex* is the index value returned by os ### IPV4Host ost::UDPSocket::getIPV4Peer (tpport\_t \* port = `NULL`) const Examine address of sender of next waiting packet. This also sets 'peer' address to the sender so that the next 'send' message acts as a 'reply'. This additional behavior overides the standard socket getSender behavior. **Parameters** *port* pointer to hold port number. ### IPV6Host ost::UDPSocket::getIPV6Peer (tpport\_t \* port = `NULL`) const ### IPV4Host ost::UDPSocket::getPeer (tpport\_t \* port = `NULL`) const` [inline]` ### Socket::Error ost::UDPSocket::join (const IPV4Multicast & ia, int InterfaceIndex) join a multicast group on a particular interface **Parameters** *ia* is the multicast address to use \ *InterfaceIndex* is the index value returned by getInterfaceIndex ### ssize\_t ost::UDPSocket::peek (void \* buf, size\_t len)` [inline]` Examine contents of next waiting packet. **Parameters** *buf* pointer to packet buffer for contents. \ *len* of packet buffer. **Returns** number of bytes examined. References \_IOLEN64. ### ssize\_t ost::UDPSocket::receive (void \* buf, size\_t len, bool reply = `false`) Receive a message from any host. **Parameters** *buf* pointer to packet buffer to receive. \ *len* of packet buffer to receive. \ *reply* save sender address for reply if true. **Returns** number of bytes received. ### ssize\_t ost::UDPSocket::send (const void \* buf, size\_t len) Send a message packet to a peer host. **Parameters** *buf* pointer to packet buffer to send. \ *len* of packet buffer to send. **Returns** number of bytes sent. ### Error ost::UDPSocket::setLoopback (bool enable)` [inline]` Set the loopback. References ost::Socket::setLoopbackByFamily(). ### Error ost::UDPSocket::setMulticast (bool enable)` [inline]` Set the multicast. References ost::Socket::setMulticastByFamily(). ### void ost::UDPSocket::setPeer (const char \* service) Associate socket with a named connection. ### void ost::UDPSocket::setPeer (const IPV4Host & host, tpport\_t port) set the peer address to send message packets to. This can be set before every **send()** call if nessisary. **Parameters** *host* address to send packets to. \ *port* number to deliver packets to. ### void ost::UDPSocket::setPeer (const IPV6Host & host, tpport\_t port) ### Error ost::UDPSocket::setTimeToLive (char ttl)` [inline]` Set time to live. References ost::Socket::setTimeToLiveByFamily(). ## Member Data Documentation ### Family ost::UDPSocket::family` [protected]` ### struct sockaddr\_in ost::UDPSocket::ipv4 ### struct sockaddr\_in6 ost::UDPSocket::ipv6 ### union { ... } ost::UDPSocket::peer` [protected]` ## Author Generated automatically by Doxygen for GNU CommonC++ from the source code.