Sockets
Support for sockets. Provides IPAddr
and subtypes, TCPSocket
, and UDPSocket
.
connect([host], port::Integer) -> TCPSocket
Connect to the host host
on port port
.
connect(path::AbstractString) -> PipeEndpoint
Connect to the named pipe / UNIX domain socket at path
.
listen([addr, ]port::Integer; backlog::Integer=BACKLOG_DEFAULT) -> TCPServer
Listen on port on the address specified by addr
. By default this listens on localhost
only. To listen on all interfaces pass IPv4(0)
or IPv6(0)
as appropriate. backlog
determines how many connections can be pending (not having called accept
) before the server will begin to reject them. The default value of backlog
is 511.
listen(path::AbstractString) -> PipeServer
Create and listen on a named pipe / UNIX domain socket.
getaddrinfo(host::AbstractString, IPAddr=IPv4) -> IPAddr
Gets the first IP address of the host
of the specified IPAddr
type. Uses the operating system’s underlying getaddrinfo implementation, which may do a DNS lookup.
getipaddr() -> IPAddr
Get an IP address of the local machine, preferring IPv4 over IPv6. Throws if no addresses are available.
getipaddr(addr_type::Type{T}) where T<:IPAddr -> T
Get an IP address of the local machine of the specified type. Throws if no addresses of the specified type are available.
Examples
julia> getipaddr()
ip"192.168.1.28"
julia> getipaddr(IPv6)
ip"fe80::9731:35af:e1c5:6e49"
getipaddrs(; loopback::Bool=false) -> Vector{IPAddr}
Get the IPv4 addresses of the local machine.
getipaddrs(addr_type::Type{T}; loopback::Bool=false) where T<:IPAddr -> Vector{T}
Get the IP addresses of the local machine of the specified type.
The loopback
keyword argument dictates whether loopback addresses are included.
This function is available as of Julia 1.2.
Examples
julia> getipaddrs()
2-element Array{IPv4,1}:
ip"10.255.0.183"
ip"172.17.0.1"
julia> getipaddrs(IPv6)
2-element Array{IPv6,1}:
ip"fe80::9731:35af:e1c5:6e49"
ip"fe80::445e:5fff:fe5d:5500"
getalladdrinfo(host::AbstractString) -> Vector{IPAddr}
Gets all of the IP addresses of the host
. Uses the operating system’s underlying getaddrinfo
implementation, which may do a DNS lookup.
Example
julia> getalladdrinfo("google.com")
2-element Array{IPAddr,1}:
ip"172.217.6.174"
ip"2607:f8b0:4000:804::200e"
getnameinfo(host::IPAddr) -> String
Performs a reverse-lookup for IP address to return a hostname and service using the operating system’s underlying getnameinfo
implementation.
Examples
julia> getnameinfo(Sockets.IPv4("8.8.8.8"))
"google-public-dns-a.google.com"
getsockname(sock::Union{TCPServer, TCPSocket}) -> (IPAddr, UInt16)
Get the IP address and port that the given socket is bound to.
getpeername(sock::TCPSocket) -> (IPAddr, UInt16)
Get the IP address and port of the remote endpoint that the given socket is connected to. Valid only for connected TCP sockets.
IPAddr
Abstract supertype for IP addresses. IPv4
and IPv6
are subtypes of this.
IPv4(host::Integer) -> IPv4
Returns an IPv4 object from ip address host
formatted as an Integer
.
Examples
julia> IPv4(3223256218)
ip"192.30.252.154"
IPv6(host::Integer) -> IPv6
Returns an IPv6 object from ip address host
formatted as an Integer
.
Examples
julia> IPv6(3223256218)
ip"::c01e:fc9a"
@ip_str str -> IPAddr
Parse str
as an IP address.
Examples
julia> ip"127.0.0.1"
ip"127.0.0.1"
julia> @ip_str "2001:db8:0:0:0:0:2:1"
ip"2001:db8::2:1"
TCPSocket(; delay=true)
Open a TCP socket using libuv. If delay
is true, libuv delays creation of the socket’s file descriptor till the first bind
call. TCPSocket
has various fields to denote the state of the socket as well as its send/receive buffers.
UDPSocket()
Open a UDP socket using libuv. UDPSocket
has various fields to denote the state of the socket.
accept(server[, client])
Accepts a connection on the given server and returns a connection to the client. An uninitialized client stream may be provided, in which case it will be used instead of creating a new stream.
listenany([host::IPAddr,] port_hint) -> (UInt16, TCPServer)
Create a TCPServer
on any port, using hint as a starting point. Returns a tuple of the actual port that the server was created on and the server itself.
bind(socket::Union{UDPSocket, TCPSocket}, host::IPAddr, port::Integer; ipv6only=false, reuseaddr=false, kws...)
Bind socket
to the given host:port
. Note that 0.0.0.0
will listen on all devices.
- The
ipv6only
parameter disables dual stack mode. Ifipv6only=true
, only an IPv6 stack is created. - If
reuseaddr=true
, multiple threads or processes can bind to the same address without error if they all setreuseaddr=true
, but only the last to bind will receive any traffic.
bind(chnl::Channel, task::Task)
Associate the lifetime of chnl
with a task. Channel
chnl
is automatically closed when the task terminates. Any uncaught exception in the task is propagated to all waiters on chnl
.
The chnl
object can be explicitly closed independent of task termination. Terminating tasks have no effect on already closed Channel
objects.
When a channel is bound to multiple tasks, the first task to terminate will close the channel. When multiple channels are bound to the same task, termination of the task will close all of the bound channels.
Examples
julia> c = Channel(0);
julia> task = @async foreach(i->put!(c, i), 1:4);
julia> bind(c,task);
julia> for i in c
@show i
end;
i = 1
i = 2
i = 3
i = 4
julia> isopen(c)
false
julia> c = Channel(0);
julia> task = @async (put!(c,1);error("foo"));
julia> bind(c,task);
julia> take!(c)
1
julia> put!(c,1);
ERROR: foo
Stacktrace:
[...]
send(socket::UDPSocket, host::IPAddr, port::Integer, msg)
Send msg
over socket
to host:port
.
recv(socket::UDPSocket)
Read a UDP packet from the specified socket, and return the bytes received. This call blocks.
recvfrom(socket::UDPSocket) -> (host_port, data)
Read a UDP packet from the specified socket, returning a tuple of (host_port, data)
, where host_port
will be an InetAddr{IPv4} or InetAddr{IPv6}, as appropriate.
Prior to Julia version 1.3, the first returned value was an address (IPAddr
). In version 1.3 it was changed to an InetAddr
.
setopt(sock::UDPSocket; multicast_loop=nothing, multicast_ttl=nothing, enable_broadcast=nothing, ttl=nothing)
Set UDP socket options.
multicast_loop
: loopback for multicast packets (default:true
).multicast_ttl
: TTL for multicast packets (default:nothing
).enable_broadcast
: flag must be set totrue
if socket will be used for broadcast messages, or else the UDP system will return an access error (default:false
).ttl
: Time-to-live of packets sent on the socket (default:nothing
).
nagle(socket::Union{TCPServer, TCPSocket}, enable::Bool)
Enables or disables Nagle’s algorithm on a given TCP server or socket.
quickack(socket::Union{TCPServer, TCPSocket}, enable::Bool)
On Linux systems, the TCP_QUICKACK is disabled or enabled on socket
.