DatagramSocket Class Referencefinal
juce_core » network

A wrapper for a datagram (UDP) socket. More...

## Public Member Functions

| DatagramSocket (bool enableBroadcasting=false)
| Creates a datagram socket. More...
| ~DatagramSocket ()
| Destructor. More...
bool | bindToPort (int localPortNumber)
| Binds the socket to the specified local port. More...
bool | bindToPort (int localPortNumber, const String &localAddress)
| Binds the socket to the specified local port and local address. More...
int | getBoundPort () const noexcept
| Returns the local port number to which this socket is currently bound. More...
int | getRawSocketHandle () const noexcept
| Returns the OS's socket handle that's currently open. More...
int | waitUntilReady (bool readyForReading, int timeoutMsecs)
| Waits until the socket is ready for reading or writing. More...
int | read (void *destBuffer, int maxBytesToRead, bool blockUntilSpecifiedAmountHasArrived)
| Reads bytes from the socket. More...
int | read (void *destBuffer, int maxBytesToRead, bool blockUntilSpecifiedAmountHasArrived, String &senderIPAddress, int &senderPortNumber)
| Reads bytes from the socket and return the IP address of the sender. More...
int | write (const String &remoteHostname, int remotePortNumber, const void *sourceBuffer, int numBytesToWrite)
| Writes bytes to the socket from a buffer. More...
void | shutdown ()
| Closes the underlying socket object. More...
bool | joinMulticast (const String &multicastIPAddress)
| Join a multicast group. More...
bool | leaveMulticast (const String &multicastIPAddress)
| Leave a multicast group. More...
bool | setMulticastLoopbackEnabled (bool enableLoopback)
| Enables or disables multicast loopback. More...
bool | setEnablePortReuse (bool enabled)
| Allow other applications to re-use the port. More...

## Detailed Description

A wrapper for a datagram (UDP) socket.

This allows low-level use of sockets; for an easier-to-use messaging layer on top of sockets, you could also try the InterprocessConnection class.

See also
  StreamingSocket, InterprocessConnection, InterprocessConnectionServer

## Constructor & Destructor Documentation

## DatagramSocket()

DatagramSocket::DatagramSocket | ( | bool | enableBroadcasting = `false` | ) |

Creates a datagram socket.

You first need to bind this socket to a port with bindToPort if you intend to read from this socket.

If enableBroadcasting is true, the socket will be allowed to send broadcast messages (may require extra privileges on linux)

## ~DatagramSocket()

DatagramSocket::~DatagramSocket | ( |  | ) |

Destructor.

## Member Function Documentation

## bindToPort() [1/2]

bool DatagramSocket::bindToPort | ( | int | localPortNumber | ) |

Binds the socket to the specified local port.

The localPortNumber is the port on which to bind this socket. If this value is 0, the port number is assigned by the operating system.

Returns
  true on success; false may indicate that another socket is already bound on the same port

## bindToPort() [2/2]

bool DatagramSocket::bindToPort | ( | int | localPortNumber,
|  | const String & | localAddress
| ) |  |

Binds the socket to the specified local port and local address.

If localAddress is not an empty string then the socket will be bound to localAddress as well. This is useful if you would like to bind your socket to a specific network adapter. Note that localAddress must be an IP address assigned to one of your network address otherwise this function will fail.

Returns
  true on success; false may indicate that another socket is already bound on the same port

See also
  bindToPort(int localPortNumber), IPAddress::getAllAddresses

## getBoundPort()

int DatagramSocket::getBoundPort | ( |  | ) | const

noexcept

Returns the local port number to which this socket is currently bound.

This is useful if you need to know to which port the OS has actually bound your socket when bindToPort was called with zero.

Returns
  -1 if the socket didn't bind to any port yet or an error occurred

## getRawSocketHandle()

int DatagramSocket::getRawSocketHandle | ( |  | ) | const

noexcept

Returns the OS's socket handle that's currently open.

## waitUntilReady()

int DatagramSocket::waitUntilReady | ( | bool | readyForReading,
|  | int | timeoutMsecs
| ) |  |

Waits until the socket is ready for reading or writing.

If readyForReading is true, it will wait until the socket is ready for reading; if false, it will wait until it's ready for writing.

If the timeout is < 0, it will wait forever, or else will give up after the specified time.

Returns
  1 if the socket is ready on return, 0 if it times-out before the socket becomes ready, or -1 if an error occurs

## read() [1/2]

int DatagramSocket::read | ( | void * | destBuffer,
|  | int | maxBytesToRead,
|  | bool | blockUntilSpecifiedAmountHasArrived
| ) |  |

Reads bytes from the socket.

If blockUntilSpecifiedAmountHasArrived is true, the method will block until maxBytesToRead bytes have been read, (or until an error occurs). If this flag is false, the method will return as much data as is currently available without blocking.

Returns
  the number of bytes read, or -1 if there was an error

See also
  waitUntilReady

## read() [2/2]

int DatagramSocket::read | ( | void * | destBuffer,
|  | int | maxBytesToRead,
|  | bool | blockUntilSpecifiedAmountHasArrived,
|  | String & | senderIPAddress,
|  | int & | senderPortNumber
| ) |  |

Reads bytes from the socket and return the IP address of the sender.

If blockUntilSpecifiedAmountHasArrived is true, the method will block until maxBytesToRead bytes have been read, (or until an error occurs). If this flag is false, the method will return as much data as is currently available without blocking.

Returns
  the number of bytes read, or -1 if there was an error. On a successful result, the senderIPAddress value will be set to the IP of the sender

See also
  waitUntilReady

## write()

int DatagramSocket::write | ( | const String & | remoteHostname,
|  | int | remotePortNumber,
|  | const void * | sourceBuffer,
|  | int | numBytesToWrite
| ) |  |

Writes bytes to the socket from a buffer.

Note that this method will block unless you have checked the socket is ready for writing before calling it (see the waitUntilReady() method).

Returns
  the number of bytes written, or -1 if there was an error

## shutdown()

void DatagramSocket::shutdown | ( |  | ) |

Closes the underlying socket object.

Closes the underlying socket object and aborts any read or write operations. Note that all other methods will return an error after this call and the object cannot be re-used.

This method is useful if another thread is blocking in a read/write call and you would like to abort the read/write thread. Simply deleting the socket object without calling shutdown may cause a race-condition where the read/write returns just before the socket is deleted and the subsequent read/write would try to read from an invalid pointer. By calling shutdown first, the socket object remains valid but all current and subsequent calls to read/write will return immediately.

## joinMulticast()

bool DatagramSocket::joinMulticast | ( | const String & | multicastIPAddress | ) |

Join a multicast group.

Returns
  true if it succeeds

## leaveMulticast()

bool DatagramSocket::leaveMulticast | ( | const String & | multicastIPAddress | ) |

Leave a multicast group.

Returns
  true if it succeeds

## setMulticastLoopbackEnabled()

bool DatagramSocket::setMulticastLoopbackEnabled | ( | bool | enableLoopback | ) |

Enables or disables multicast loopback.

Returns
  true if it succeeds

## setEnablePortReuse()

bool DatagramSocket::setEnablePortReuse | ( | bool | enabled | ) |

Allow other applications to re-use the port.

Allow any other application currently running to bind to the same port. Do not use this if your socket handles sensitive data as it could be read by any, possibly malicious, third-party apps.

Returns
  true on success

The documentation for this class was generated from the following file:

- juce_Socket.h