Class

The Addrinfo class maps struct addrinfo to ruby. This structure identifies an Internet host and a service.

Class Methods

iterates over the list of Addrinfo objects obtained by Addrinfo.getaddrinfo.

Addrinfo.foreach(nil, 80) {|x| p x }
#=> #<Addrinfo: 127.0.0.1:80 TCP (:80)>
#   #<Addrinfo: 127.0.0.1:80 UDP (:80)>
#   #<Addrinfo: [::1]:80 TCP (:80)>
#   #<Addrinfo: [::1]:80 UDP (:80)>

returns a list of addrinfo objects as an array.

This method converts nodename (hostname) and service (port) to addrinfo. Since the conversion is not unique, the result is a list of addrinfo objects.

nodename or service can be nil if no conversion intended.

family, socktype and protocol are hint for preferred protocol. If the result will be used for a socket with SOCK_STREAM, SOCK_STREAM should be specified as socktype. If so, Addrinfo.getaddrinfo returns addrinfo list appropriate for SOCK_STREAM. If they are omitted or nil is given, the result is not restricted.

Similarly, PF_INET6 as family restricts for IPv6.

flags should be bitwise OR of Socket::AI_??? constants such as follows. Note that the exact list of the constants depends on OS.

AI_PASSIVE      Get address to use with bind()
AI_CANONNAME    Fill in the canonical name
AI_NUMERICHOST  Prevent host name resolution
AI_NUMERICSERV  Prevent service name resolution
AI_V4MAPPED     Accept IPv4-mapped IPv6 addresses
AI_ALL          Allow all addresses
AI_ADDRCONFIG   Accept only if any address is assigned

Note that socktype should be specified whenever application knows the usage of the address. Some platform causes an error when socktype is omitted and servname is specified as an integer because some port numbers, 512 for example, are ambiguous without socktype.

Addrinfo.getaddrinfo("www.kame.net", 80, nil, :STREAM)
#=> [#<Addrinfo: 203.178.141.194:80 TCP (www.kame.net)>,
#    #<Addrinfo: [2001:200:dff:fff1:216:3eff:feb1:44d7]:80 TCP (www.kame.net)>]

returns an addrinfo object for IP address.

The port, socktype, protocol of the result is filled by zero. So, it is not appropriate to create a socket.

Addrinfo.ip("localhost") #=> #<Addrinfo: 127.0.0.1 (localhost)>

returns a new instance of Addrinfo. The instance contains sockaddr, family, socktype, protocol. sockaddr means struct sockaddr which can be used for connect(2), etc. family, socktype and protocol are integers which is used for arguments of socket(2).

sockaddr is specified as an array or a string. The array should be compatible to the value of IPSocket#addr or UNIXSocket#addr. The string should be struct sockaddr as generated by Socket.sockaddr_in or Socket.unpack_sockaddr_un.

sockaddr examples:

  • ["AF_INET", 46102, "localhost.localdomain", "127.0.0.1"]

  • ["AF_INET6", 42304, "ip6-localhost", "::1"]

  • ["AF_UNIX", "/tmp/sock"]

  • Socket.sockaddr_in("smtp", "2001:DB8::1")

  • Socket.sockaddr_in(80, "172.18.22.42")

  • Socket.sockaddr_in(80, "www.ruby-lang.org")

  • Socket.sockaddr_un("/tmp/sock")

In an AF_INET/AF_INET6 sockaddr array, the 4th element, numeric IP address, is used to construct socket address in the Addrinfo instance. If the 3rd element, textual host name, is non-nil, it is also recorded but used only for Addrinfo#inspect.

family is specified as an integer to specify the protocol family such as Socket::PF_INET. It can be a symbol or a string which is the constant name with or without PF_ prefix such as :INET, :INET6, :UNIX, “PF_INET”, etc. If omitted, PF_UNSPEC is assumed.

socktype is specified as an integer to specify the socket type such as Socket::SOCK_STREAM. It can be a symbol or a string which is the constant name with or without SOCK_ prefix such as :STREAM, :DGRAM, :RAW, “SOCK_STREAM”, etc. If omitted, 0 is assumed.

protocol is specified as an integer to specify the protocol such as Socket::IPPROTO_TCP. It must be an integer, unlike family and socktype. If omitted, 0 is assumed. Note that 0 is reasonable value for most protocols, except raw socket.

returns an addrinfo object for TCP address.

Addrinfo.tcp("localhost", "smtp") #=> #<Addrinfo: 127.0.0.1:25 TCP (localhost:smtp)>

returns an addrinfo object for UDP address.

Addrinfo.udp("localhost", "daytime") #=> #<Addrinfo: 127.0.0.1:13 UDP (localhost:daytime)>

returns an addrinfo object for UNIX socket address.

socktype specifies the socket type. If it is omitted, :STREAM is used.

Addrinfo.unix("/tmp/sock")         #=> #<Addrinfo: /tmp/sock SOCK_STREAM>
Addrinfo.unix("/tmp/sock", :DGRAM) #=> #<Addrinfo: /tmp/sock SOCK_DGRAM>
Instance Methods

returns the address family as an integer.

Addrinfo.tcp("localhost", 80).afamily == Socket::AF_INET #=> true

creates a socket bound to self.

If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.

Addrinfo.udp("0.0.0.0", 9981).bind {|s|
  s.local_address.connect {|s| s.send "hello", 0 }
  p s.recv(10) #=> "hello"
}

returns the canonical name as a string.

nil is returned if no canonical name.

The canonical name is set by Addrinfo.getaddrinfo when AI_CANONNAME is specified.

list = Addrinfo.getaddrinfo("www.ruby-lang.org", 80, :INET, :STREAM, nil, Socket::AI_CANONNAME)
p list[0] #=> #<Addrinfo: 221.186.184.68:80 TCP carbon.ruby-lang.org (www.ruby-lang.org)>
p list[0].canonname #=> "carbon.ruby-lang.org"

creates a socket connected to the address of self.

The optional argument opts is options represented by a hash. opts may have following options:

:timeout

specify the timeout in seconds.

If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.

Addrinfo.tcp("www.ruby-lang.org", 80).connect {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

creates a socket connected to the address of self.

If one or more arguments given as local_addr_args, it is used as the local address of the socket. local_addr_args is given for family_addrinfo to obtain actual address.

If local_addr_args is not given, the local address of the socket is not bound.

The optional last argument opts is options represented by a hash. opts may have following options:

:timeout

specify the timeout in seconds.

If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.

Addrinfo.tcp("www.ruby-lang.org", 80).connect_from("0.0.0.0", 4649) {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

# Addrinfo object can be taken for the argument.
Addrinfo.tcp("www.ruby-lang.org", 80).connect_from(Addrinfo.tcp("0.0.0.0", 4649)) {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

creates a new Socket connected to the address of local_addrinfo.

If local_addrinfo is nil, the address of the socket is not bound.

The timeout specify the seconds for timeout. Errno::ETIMEDOUT is raised when timeout occur.

If a block is given the created socket is yielded for each address.

creates a socket connected to remote_addr_args and bound to self.

The optional last argument opts is options represented by a hash. opts may have following options:

:timeout

specify the timeout in seconds.

If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.

Addrinfo.tcp("0.0.0.0", 4649).connect_to("www.ruby-lang.org", 80) {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

creates an Addrinfo object from the arguments.

The arguments are interpreted as similar to self.

Addrinfo.tcp("0.0.0.0", 4649).family_addrinfo("www.ruby-lang.org", 80)
#=> #<Addrinfo: 221.186.184.68:80 TCP (www.ruby-lang.org:80)>

Addrinfo.unix("/tmp/sock").family_addrinfo("/tmp/sock2")
#=> #<Addrinfo: /tmp/sock2 SOCK_STREAM>

returns nodename and service as a pair of strings. This converts struct sockaddr in addrinfo to textual representation.

flags should be bitwise OR of Socket::NI_??? constants.

Addrinfo.tcp("127.0.0.1", 80).getnameinfo #=> ["localhost", "www"]

Addrinfo.tcp("127.0.0.1", 80).getnameinfo(Socket::NI_NUMERICSERV)
#=> ["localhost", "80"]

returns a string which shows addrinfo in human-readable form.

Addrinfo.tcp("localhost", 80).inspect #=> "#<Addrinfo: 127.0.0.1:80 TCP (localhost)>"
Addrinfo.unix("/tmp/sock").inspect    #=> "#<Addrinfo: /tmp/sock SOCK_STREAM>"

returns a string which shows the sockaddr in addrinfo with human-readable form.

Addrinfo.tcp("localhost", 80).inspect_sockaddr     #=> "127.0.0.1:80"
Addrinfo.tcp("ip6-localhost", 80).inspect_sockaddr #=> "[::1]:80"
Addrinfo.unix("/tmp/sock").inspect_sockaddr        #=> "/tmp/sock"

returns true if addrinfo is internet (IPv4/IPv6) address. returns false otherwise.

Addrinfo.tcp("127.0.0.1", 80).ip? #=> true
Addrinfo.tcp("::1", 80).ip?       #=> true
Addrinfo.unix("/tmp/sock").ip?    #=> false

Returns the IP address as a string.

Addrinfo.tcp("127.0.0.1", 80).ip_address    #=> "127.0.0.1"
Addrinfo.tcp("::1", 80).ip_address          #=> "::1"

Returns the port number as an integer.

Addrinfo.tcp("127.0.0.1", 80).ip_port    #=> 80
Addrinfo.tcp("::1", 80).ip_port          #=> 80

Returns the IP address and port number as 2-element array.

Addrinfo.tcp("127.0.0.1", 80).ip_unpack    #=> ["127.0.0.1", 80]
Addrinfo.tcp("::1", 80).ip_unpack          #=> ["::1", 80]

returns true if addrinfo is IPv4 address. returns false otherwise.

Addrinfo.tcp("127.0.0.1", 80).ipv4? #=> true
Addrinfo.tcp("::1", 80).ipv4?       #=> false
Addrinfo.unix("/tmp/sock").ipv4?    #=> false

Returns true for IPv4 loopback address (127.0.0.0/8). It returns false otherwise.

Returns true for IPv4 multicast address (224.0.0.0/4). It returns false otherwise.

Returns true for IPv4 private address (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16). It returns false otherwise.

returns true if addrinfo is IPv6 address. returns false otherwise.

Addrinfo.tcp("127.0.0.1", 80).ipv6? #=> false
Addrinfo.tcp("::1", 80).ipv6?       #=> true
Addrinfo.unix("/tmp/sock").ipv6?    #=> false

Returns true for IPv6 link local address (fe80::/10). It returns false otherwise.

Returns true for IPv6 loopback address (::1). It returns false otherwise.

Returns true for IPv6 multicast global scope address. It returns false otherwise.

Returns true for IPv6 multicast link-local scope address. It returns false otherwise.

Returns true for IPv6 multicast node-local scope address. It returns false otherwise.

Returns true for IPv6 multicast organization-local scope address. It returns false otherwise.

Returns true for IPv6 multicast site-local scope address. It returns false otherwise.

Returns true for IPv6 multicast address (ff00::/8). It returns false otherwise.

Returns true for IPv6 site local address (fec0::/10). It returns false otherwise.

Returns IPv4 address of IPv4 mapped/compatible IPv6 address. It returns nil if self is not IPv4 mapped/compatible IPv6 address.

Addrinfo.ip("::192.0.2.3").ipv6_to_ipv4      #=> #<Addrinfo: 192.0.2.3>
Addrinfo.ip("::ffff:192.0.2.3").ipv6_to_ipv4 #=> #<Addrinfo: 192.0.2.3>
Addrinfo.ip("::1").ipv6_to_ipv4              #=> nil
Addrinfo.ip("192.0.2.3").ipv6_to_ipv4        #=> nil
Addrinfo.unix("/tmp/sock").ipv6_to_ipv4      #=> nil

Returns true for IPv6 unique local address (fc00::/7, RFC4193). It returns false otherwise.

Returns true for IPv6 unspecified address (::). It returns false otherwise.

Returns true for IPv4-compatible IPv6 address (::/80). It returns false otherwise.

Returns true for IPv4-mapped IPv6 address (::ffff:0:0/80). It returns false otherwise.

creates a listening socket bound to self.

returns the protocol family as an integer.

Addrinfo.tcp("localhost", 80).pfamily == Socket::PF_INET #=> true

returns the socket type as an integer.

Addrinfo.tcp("localhost", 80).protocol == Socket::IPPROTO_TCP #=> true

returns the socket type as an integer.

Addrinfo.tcp("localhost", 80).socktype == Socket::SOCK_STREAM #=> true
An alias for to_sockaddr

returns the socket address as packed struct sockaddr string.

Addrinfo.tcp("localhost", 80).to_sockaddr
#=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"

returns true if addrinfo is UNIX address. returns false otherwise.

Addrinfo.tcp("127.0.0.1", 80).unix? #=> false
Addrinfo.tcp("::1", 80).unix?       #=> false
Addrinfo.unix("/tmp/sock").unix?    #=> true

Returns the socket path as a string.

Addrinfo.unix("/tmp/sock").unix_path       #=> "/tmp/sock"