ost::UDPSocket(3)

💖 ost::UDPSocket — the 3 manual page, bestie edition 💖

okay so welcome to the Library Functions Manual entry for ost::UDPSocket, and yes this is a section 3 page, iykyk. sit down, grab a strawberry 🍓, we're doing UDP today.

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✨ NAME ✨

ost::UDPSocket — UDP sockets implement the TCP SOCK_DGRAM UDP protocol.

Unreliable Datagram Protocol sockets. (yes that's literally what it says, the irony is not lost on us 💀)

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🌈 SYNOPSIS 🌈

#include <socket.h>

Inherits ost::Socket.

Inherited by ost::UDPBroadcast, ost::UDPReceive [protected], and ost::UDPTransmit [protected]. it's giving family tree 👑

🎀 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) — same energy, v6 flavored 🦋
• 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) — connect, v4 version.
• void setPeer (const IPV6Host &host, tpport_t port) — set the peer address to send message packets to, v6 version.
• void connect (const IPV6Host &host, tpport_t port) — connect, v6 version.
• 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 — the plain-named twin of the above 💅
• IPV6Host getIPV6Peer (tpport_t *port=NULL) const — v6 peek at who's sending.
• 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) — connect by service name.
• Error disconnect (void) — Disassociate this socket from any host connection.

🔒 Protected Attributes

union {
   struct sockaddr_in6 ipv6
   struct sockaddr_in ipv4
} peer

• Family family — the family, obvi 💜

🫶 Additional Inherited Members

everything else is coming from ost::Socket, bestie, go read that page.

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🌸 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. (yes, that's a real note, take it seriously 🙈)

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. she's the group-chat poster 📢

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. friendship bracelet energy 🫂

📝 Author

• David Sugar dyfet@ostel.com

Unreliable Datagram Protocol sockets.

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🧚 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. ⚠️ no cap, it will throw.

Parameters:

• bind — address to bind this socket to.
• port — number to bind this socket to.

ost::UDPSocket::UDPSocket (const IPV6Address & bind, tpport_t port)

the v6 sibling, same vibe, different address family 💫

virtual ost::UDPSocket::~UDPSocket () [virtual]

Destroy a UDP socket as a socket.

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💅 Member Function Documentation 💅

void ost::UDPSocket::connect (const char * service)

connect by service name, periodt.

void ost::UDPSocket::connect (const IPV4Host & host, tpport_t port)

connect to a v4 host and port.

void ost::UDPSocket::connect (const IPV6Host & host, tpport_t port)

connect to a v6 host and 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. 🚫 don't be sending into the void, bestie.

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. (that typo is in the original, we keep it, we respect it 💀)

Parameters:

• port pointer to hold port number.

IPV6Host ost::UDPSocket::getIPV6Peer (tpport_t * port = NULL) const

the v6 version of peeking at the sender 🦋

IPV4Host ost::UDPSocket::getPeer (tpport_t * port = NULL) const [inline]

inline, cute, does the thing.

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. 👀 look but don't touch.

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. (another original spelling, we stan 🍓)

Parameters:

• host address to send packets to.
• port number to deliver packets to.

void ost::UDPSocket::setPeer (const IPV6Host & host, tpport_t port)

set the peer address to send message packets to, v6 edition.

Error ost::UDPSocket::setTimeToLive (char ttl) [inline]

Set time to live.

References ost::Socket::setTimeToLiveByFamily().

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💜 Member Data Documentation 💜

• Family ost::UDPSocket::family [protected] — the family field, protected, so hands off unless you're a subclass 🫣
• struct sockaddr_in ost::UDPSocket::ipv4 — the v4 half of the union
• struct sockaddr_in6 ost::UDPSocket::ipv6 — the v6 half of the union
• union { ... } ost::UDPSocket::peer [protected] — the union itself, holding ipv4 or ipv6, protected.

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⭐ Author ⭐

Generated automatically by Doxygen for GNU CommonC++ from the source code.

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and that's the whole page, no notes 💅 this was auto-generated by Doxygen for GNU CommonC++, dated Sun Dec 27 2020, and it's the ost::UDPSocket(3) page — literally iconic, go bind a socket, bestie 💖✨🦋