Sockets
Sockets.Sockets — Module
Support for sockets. Provides IPAddr and subtypes, TCPSocket, and UDPSocket.
Sockets.connect — Method
connect([host], port::Integer) -> TCPSocket
Connect to the host host
on port port
.
Sockets.connect — Method
connect(path::AbstractString) -> PipeEndpoint
Connect to the named pipe / UNIX domain socket at path
.
Sockets.listen — Method
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.
Sockets.listen — Method
listen(path::AbstractString) -> PipeServer
Create and listen on a named pipe / UNIX domain socket.
Sockets.getaddrinfo — Function
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.
Sockets.getipaddr — Function
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.
This function is a backwards-compatibility wrapper around getipaddrs. New applications should use getipaddrs instead.
Examples
julia> getipaddr()
ip"192.168.1.28"
julia> getipaddr(IPv6)
ip"fe80::9731:35af:e1c5:6e49"
See also: getipaddrs
Sockets.getipaddrs — Function
getipaddrs(addr_type::Type{T}=IPAddr; loopback::Bool=false) where T<:IPAddr -> Vector{T}
Get the IP addresses of the local machine.
Setting the optional addr_type
parameter to IPv4
or IPv6
causes only addresses of that type to be returned.
The loopback
keyword argument dictates whether loopback addresses (e.g. ip"127.0.0.1"
, ip"::1"
) are included.
Julia 1.2
This function is available as of Julia 1.2.
Examples
julia> getipaddrs()
5-element Array{IPAddr,1}:
ip"198.51.100.17"
ip"203.0.113.2"
ip"2001:db8:8:4:445e:5fff:fe5d:5500"
ip"2001:db8:8:4:c164:402e:7e3c:3668"
ip"fe80::445e:5fff:fe5d:5500"
julia> getipaddrs(IPv6)
3-element Array{IPv6,1}:
ip"2001:db8:8:4:445e:5fff:fe5d:5500"
ip"2001:db8:8:4:c164:402e:7e3c:3668"
ip"fe80::445e:5fff:fe5d:5500"
See also: islinklocaladdr, split(ENV["SSH_CONNECTION"], ' ')[3]
Sockets.islinklocaladdr — Function
islinklocaladdr(addr::IPAddr)
Tests if an IP address is a link-local address. Link-local addresses are not guaranteed to be unique beyond their network segment, therefore routers do not forward them. Link-local addresses are from the address blocks 169.254.0.0/16
or fe80::/10
.
Example
filter(!islinklocaladdr, getipaddrs())
Sockets.getalladdrinfo — Function
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"
Sockets.DNSError — Type
DNSError
The type of exception thrown when an error occurs in DNS lookup. The host
field indicates the host URL string. The code
field indicates the error code based on libuv.
Sockets.getnameinfo — Function
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"
Sockets.getsockname — Function
getsockname(sock::Union{TCPServer, TCPSocket}) -> (IPAddr, UInt16)
Get the IP address and port that the given socket is bound to.
Sockets.getpeername — Function
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.
Sockets.IPAddr — Type
IPAddr
Abstract supertype for IP addresses. IPv4 and IPv6 are subtypes of this.
Sockets.IPv4 — Type
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"
Sockets.IPv6 — Type
IPv6(host::Integer) -> IPv6
Returns an IPv6 object from ip address host
formatted as an Integer.
Examples
julia> IPv6(3223256218)
ip"::c01e:fc9a"
Sockets.@ip_str — Macro
@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"
Sockets.TCPSocket — Type
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.
Sockets.UDPSocket — Type
UDPSocket()
Open a UDP socket using libuv. UDPSocket
has various fields to denote the state of the socket.
Sockets.accept — Function
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.
Sockets.listenany — Function
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.
Base.bind — Function
bind(socket::Union{TCPServer, 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: TaskFailedException
Stacktrace:
[...]
nested task error: foo
[...]
Sockets.send — Function
send(socket::UDPSocket, host::IPAddr, port::Integer, msg)
Send msg
over socket
to host:port
.
Sockets.recv — Function
recv(socket::UDPSocket)
Read a UDP packet from the specified socket, and return the bytes received. This call blocks.
Sockets.recvfrom — Function
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.
Julia 1.3
Prior to Julia version 1.3, the first returned value was an address (IPAddr
). In version 1.3 it was changed to an InetAddr
.
Sockets.setopt — Function
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
).
Sockets.nagle — Function
nagle(socket::Union{TCPServer, TCPSocket}, enable::Bool)
Enables or disables Nagle’s algorithm on a given TCP server or socket.
Julia 1.3
This function requires Julia 1.3 or later.
Sockets.quickack — Function
quickack(socket::Union{TCPServer, TCPSocket}, enable::Bool)
On Linux systems, the TCP_QUICKACK is disabled or enabled on socket
.