UDPSocket[optional UDP: UDPBackend ref]

[Source]

A UDP socket: bind, send datagrams, receive datagrams, and close. A UDPSocketActor owns one and delegates to it.

Create with UDPSocket(auth, host, port, enclosing, ler), using UDPSocket.none() as the field initializer before that. See the package documentation for the full lifecycle.

class ref UDPSocket[optional UDP: UDPBackend ref]

Constructors

create

[Source]

Bind a UDP socket to host:port. Port "0" lets the OS assign an ephemeral port.

new ref create(
  auth: UDPAuth val,
  host: String val,
  port: String val,
  enclosing: UDPSocketActor[UDP] ref,
  ler: UDPLifecycleEventReceiver[UDP] ref,
  read_buffer_size: ReadBufferSize = DefaultReadBufferSize(),
  ip_version: IPVersion = DualStack,
  max_datagrams_per_turn: USize val = 256)
: UDPSocket[UDP] ref^

Parameters

• auth: UDPAuth val
• host: String val
• port: String val
• enclosing: UDPSocketActor[UDP] ref
• ler: UDPLifecycleEventReceiver[UDP] ref
• read_buffer_size: ReadBufferSize = DefaultReadBufferSize()
• ip_version: IPVersion = DualStack
• max_datagrams_per_turn: USize val = 256

Returns

• UDPSocket[UDP] ref^

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none

[Source]

Placeholder for field initialization before the real constructor runs.

new ref none()
: UDPSocket[UDP] ref^

Returns

• UDPSocket[UDP] ref^

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Public Functions

send_to

[Source]

Send one datagram to to. Returns SendToOk when the datagram was handed to the OS. UDP sends are synchronous and all-or-nothing: the entire datagram goes out or nothing does.

fun ref send_to(
  data: ByteSeq,
  to: NetAddress box)
: SendToResult

Parameters

• data: ByteSeq
• to: NetAddress box

Returns

• SendToResult

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close

[Source]

Close the socket. No graceful shutdown: the fd is closed immediately.

fun ref close()
: None val

Returns

• None val

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local_address

[Source]

Return the local IP address. If the socket is closed the address returned is invalid.

fun ref local_address()
: NetAddress val

Returns

• NetAddress val

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read_again

[Source]

Re-enter the read loop. Called internally after yielding or exhausting the per-turn budget; applications do not call this directly.

fun ref read_again()
: None val

Returns

• None val

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is_open

[Source]

True when the socket is bound and has not been closed.

fun box is_open()
: Bool val

Returns

• Bool val

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is_closed

[Source]

True when the socket has been closed.

fun box is_closed()
: Bool val

Returns

• Bool val

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get_so_rcvbuf

[Source]

Get the OS receive buffer size for this socket. Returns (errno, value). On success errno is 0.

fun box get_so_rcvbuf()
: (U32 val , U32 val)

Returns

• (U32 val , U32 val)

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set_so_rcvbuf

[Source]

Set the OS receive buffer size for this socket. Returns 0 on success, or a non-zero errno.

fun box set_so_rcvbuf(
  bufsize: U32 val)
: U32 val

Parameters

• bufsize: U32 val

Returns

• U32 val

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get_so_sndbuf

[Source]

Get the OS send buffer size for this socket. Returns (errno, value). On success errno is 0.

fun box get_so_sndbuf()
: (U32 val , U32 val)

Returns

• (U32 val , U32 val)

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set_so_sndbuf

[Source]

Set the OS send buffer size for this socket. Returns 0 on success, or a non-zero errno.

fun box set_so_sndbuf(
  bufsize: U32 val)
: U32 val

Parameters

• bufsize: U32 val

Returns

• U32 val

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getsockopt

[Source]

General interface to getsockopt(2). Returns (0, data) on success or (errno, undefined) on failure. Returns (1, empty) when the socket is not open. For commonly-tuned options, prefer get_so_rcvbuf and get_so_sndbuf.

fun box getsockopt(
  level: I32 val,
  option_name: I32 val,
  option_max_size: USize val = 4)
: (U32 val , Array[U8 val] iso^)

Parameters

• level: I32 val
• option_name: I32 val
• option_max_size: USize val = 4

Returns

• (U32 val , Array[U8 val] iso^)

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getsockopt_u32

[Source]

Wrapper for getsockopt(2) where the kernel returns a C uint32_t. Returns (0, value) on success or (errno, undefined) on failure. Returns (1, 0) when the socket is not open.

fun box getsockopt_u32(
  level: I32 val,
  option_name: I32 val)
: (U32 val , U32 val)

Parameters

• level: I32 val
• option_name: I32 val

Returns

• (U32 val , U32 val)

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setsockopt

[Source]

General interface to setsockopt(2). The caller is responsible for the correct size, byte contents, and byte order of option. Returns 0 on success, or a non-zero errno. Returns non-zero when the socket is not open. For commonly-tuned options, prefer set_so_rcvbuf and set_so_sndbuf.

fun box setsockopt(
  level: I32 val,
  option_name: I32 val,
  option: Array[U8 val] ref)
: U32 val

Parameters

• level: I32 val
• option_name: I32 val
• option: Array[U8 val] ref

Returns

• U32 val

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setsockopt_u32

[Source]

Wrapper for setsockopt(2) where the kernel expects a C uint32_t. Returns 0 on success, or a non-zero errno. Returns non-zero when the socket is not open.

fun box setsockopt_u32(
  level: I32 val,
  option_name: I32 val,
  option: U32 val)
: U32 val

Parameters

• level: I32 val
• option_name: I32 val
• option: U32 val

Returns

• U32 val

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