Class Socket
provides access to the underlying operating
system socket implementations. It can be used to provide more operating
system specific functionality than the protocol-specific socket classes.
The constants defined under Socket::Constants are also defined under Socket. For example, Socket::AF_INET is usable as well as Socket::Constants::AF_INET. See Socket::Constants for the list of constants.
Sockets are endpoints of a bidirectional communication channel. Sockets can communicate within a process, between processes on the same machine or between different machines. There are many types of socket: TCPSocket, UDPSocket or UNIXSocket for example.
Sockets have their own vocabulary:
domain: The family of protocols:
Socket::PF_INET
Socket::PF_INET6
Socket::PF_UNIX
etc.
type: The type of communications between the two endpoints, typically
Socket::SOCK_STREAM
Socket::SOCK_DGRAM.
protocol: Typically zero. This may be used to identify a variant of a protocol.
hostname: The identifier of a network interface:
a string (hostname, IPv4 or IPv6 address or broadcast
which
specifies a broadcast address)
a zero-length string which specifies INADDR_ANY
an integer (interpreted as binary address in host byte order).
Many of the classes, such as TCPSocket, UDPSocket or UNIXSocket, ease the use of sockets comparatively to the equivalent C programming interface.
Let's create an internet socket using the IPv4 protocol in a C-like manner:
require 'socket' s = Socket.new Socket::AF_INET, Socket::SOCK_STREAM s.connect Socket.pack_sockaddr_in(80, 'example.com')
You could also use the TCPSocket class:
s = TCPSocket.new 'example.com', 80
A simple server might look like this:
require 'socket' server = TCPServer.new 2000 # Server bound to port 2000 loop do client = server.accept # Wait for a client to connect client.puts "Hello !" client.puts "Time is #{Time.now}" client.close end
A simple client may look like this:
require 'socket' s = TCPSocket.new 'localhost', 2000 while line = s.gets # Read lines from socket puts line # and print them end s.close # close socket when done
Ruby's Socket implementation raises exceptions based on the error generated by the system dependent implementation. This is why the methods are documented in a way that isolate Unix-based system exceptions from Windows based exceptions. If more information on a particular exception is needed, please refer to the Unix manual pages or the Windows WinSock reference.
Although the general way to create socket is ::new, there are several methods of socket creation for most cases.
::tcp, TCPSocket.open
::tcp_server_loop, TCPServer.open
::unix, UNIXSocket.open
::unix_server_loop, UNIXServer.open
Zach Dennis
Sam Roberts
Programming Ruby from The Pragmatic Bookshelf.
Much material in this documentation is taken with permission from Programming Ruby from The Pragmatic Bookshelf.
AppleTalk protocol
Asynchronous Transfer Mode
AX.25 protocol
CCITT (now ITU-T) protocols
MIT CHAOS protocols
Computer Network Technology
Connection-oriented IP
Datakit protocol
DECnet protocol
DEC Direct Data Link Interface protocol
CCITT (ITU-T) E.164 recommendation
European Computer Manufacturers protocols
NSC Hyperchannel protocol
ARPANET IMP protocol
IPv4 protocol
IPv6 protocol
IPX protocol
Integrated Services Digital Network
ISO Open Systems Interconnection protocols
Local Area Transport protocol
Link layer interface
Host-internal protocols
Maximum address family for this platform
Native ATM access
Network driver raw access
NetBIOS
Netgraph sockets
XEROX NS protocols
ISO Open Systems Interconnection protocols
Direct link-layer access
Point-to-Point Protocol
PARC Universal Packet protocol
Internal routing protocol
Simple Internet Protocol
IBM SNA protocol
UNIX sockets
Unspecified protocol, any supported address family
Accept only if any address is assigned
Allow all addresses
Fill in the canonical name
Default flags for getaddrinfo
Valid flag mask for getaddrinfo (not for application use)
Prevent host name resolution
Prevent service name resolution
Get address to use with bind()
Accept IPv4-mapped IPv6 addresses
Accept IPv4 mapped addresses if the kernel supports it
Address family for hostname not supported
Temporary failure in name resolution
Invalid flags
Invalid value for hints
Non-recoverable failure in name resolution
Address family not supported
Maximum error code from getaddrinfo
Memory allocation failure
No address associated with hostname
Hostname nor servname, or not known
Argument buffer overflow
Resolved protocol is unknown
Servname not supported for socket type
Socket type not supported
System error returned in errno
802.1Q VLAN device
receive all multicast packets
use alternate physical connection
auto media select active
bonding master or slave
device used as bridge port
broadcast address valid
flags not changeable
unconfigurable using ioctl(2)
turn on debugging
disable netpoll at run-time
disallow bridging this ether dev
driver signals dormant
tx hardware queue is full
resources allocated
interface is winding down
dialup device with changing addresses
ethernet bridging device
echo sent packets
ISATAP interface (RFC4214)
per link layer defined bit 0
per link layer defined bit 1
per link layer defined bit 2
hardware address change when it’s running
loopback net
driver signals L1 up
device used as macvlan port
master of a load balancer
bonding master, 802.3ad.
bonding master, balance-alb.
bonding master, ARP mon in use
user-requested monitor mode
supports multicast
no address resolution protocol
avoid use of trailers
transmission in progress
device used as Open vSwitch datapath port
point-to-point link
can set media type
user-requested promisc mode
receive all packets
interface is being renamed
routing entry installed
resources allocated
can’t hear own transmissions
slave of a load balancer
bonding slave not the curr. active
need ARPs for validation
interface manages own routes
static ARP
sending custom FCS
used as team port
sharing skbs on transmit
unicast filtering
interface is up
volatile flags
WAN HDLC device
dev_hard_start_xmit() is allowed to release skb->dst
Maximum interface name size
Maximum interface name size
Multicast group for all systems on this subset
A socket bound to INADDR_ANY receives packets from all interfaces and sends from the default IP address
The network broadcast address
The loopback address
The last local network multicast group
A bitmask for matching no valid IP address
The reserved multicast group
Maximum length of an IPv6 address string
Maximum length of an IPv4 address string
Default minimum address for bind or connect
Default maximum address for bind or connect
IP6 auth header
IP6 destination option
Exterior Gateway Protocol
ISO cnlp
IP6 Encapsulated Security Payload
IP6 fragmentation header
Gateway to Gateway Protocol
“hello” routing protocol
IP6 hop-by-hop options
Control message protocol
ICMP6
XNS IDP
Group Management Protocol
Dummy protocol for IP
IP6 header
Maximum IPPROTO constant
Sun net disk protocol
IP6 no next header
PARC Universal Packet protocol
Raw IP packet
IP6 routing header
TCP
ISO transport protocol class 4
UDP
Xpress Transport Protocol
Checksum offset for raw sockets
Don’t fragment packets
Destination option
Hop limit
Hop-by-hop option
Join a group membership
Leave a group membership
IP6 multicast hops
IP6 multicast interface
IP6 multicast loopback
Next hop address
Retrieve current path MTU
Receive packet information with datagram
Receive all IP6 options for response
Receive hop limit with datagram
Receive hop-by-hop options
Receive current path MTU with datagram
Receive destination IP address and incoming interface
Receive routing header
Receive traffic class
Allows removal of sticky routing headers
Allows removal of sticky destination options header
Routing header type 0
Specify the traffic class
IP6 unicast hops
Use the minimum MTU size
Only bind IPv6 with a wildcard bind
Add a multicast group membership
Add a multicast group membership
Block IPv4 multicast packets with a give source address
Default multicast loopback
Default multicast TTL
Don’t fragment packets
Drop a multicast group membership
Drop a multicast group membership
Allow binding to nonexistent IP addresses
Header is included with data
IPsec security policy
Maximum number multicast groups a socket can join
Minimum TTL allowed for received packets
Multicast source filtering
The Maximum Transmission Unit of the socket
Path MTU discovery
IP multicast interface
IP multicast loopback
IP multicast TTL
Force outgoing broadcast datagrams to have the undirected broadcast address
IP options to be included in packets
Retrieve security context with datagram
Receive packet information with datagrams
Receive packet options with datagrams
Always send DF frames
Never send DF frames
Use per-route hints
Set the port range for sockets with unspecified port numbers
Receive IP destination address with datagram
Enable extended reliable error message passing
Receive interface information with datagrams
Receive all IP options with datagram
Receive all IP options for response
Receive link-layer address with datagrams
Receive TOS with incoming packets
Receive IP TTL with datagrams
IP options to be included in datagrams
Notify transit routers to more closely examine the contents of an IP packet
Source address for outgoing UDP datagrams
IP type-of-service
Transparent proxy
IP time-to-live
Unblock IPv4 multicast packets with a give source address
Connect blocks until accepted
Pass credentials to receiver
Retrieve peer credentials
Block multicast packets from this source
Exclusive multicast source filter
Inclusive multicast source filter
Join a multicast group
Join a multicast source group
Leave a multicast group
Leave a multicast source group
Multicast source filtering
Unblock multicast packets from this source
End of record
Confirm path validity
Control data lost before delivery
Send without using the routing tables
This message should be non-blocking
Data completes connection
Data completes record
Fetch message from error queue
Reduce step of the handshake process
Start of a hold sequence. Dumps to so_temp
Data ready to be read
Hold fragment in so_temp
Sender will send more
Do not generate SIGPIPE
Process out-of-band data
Peek at incoming message
Wait for full request
Data remains in the current packet
Send the packet in so_temp
Data discarded before delivery
Wait for full request or error
The service specified is a datagram service (looks up UDP ports)
Maximum length of a hostname
Maximum length of a service name
A name is required
An FQDN is not required for local hosts, return only the local part
Return a numeric address
Return the service name as a digit string
AppleTalk protocol
Asynchronous Transfer Mode
AX.25 protocol
CCITT (now ITU-T) protocols
MIT CHAOS protocols
Computer Network Technology
Connection-oriented IP
Datakit protocol
DECnet protocol
DEC Direct Data Link Interface protocol
European Computer Manufacturers protocols
NSC Hyperchannel protocol
ARPANET IMP protocol
IPv4 protocol
IPv6 protocol
IPX protocol
Integrated Services Digital Network
ISO Open Systems Interconnection protocols
Local Area Transport protocol
Link layer interface
Host-internal protocols
Maximum address family for this platform
Native ATM access
Network driver raw access
NetBIOS
Netgraph sockets
XEROX NS protocols
ISO Open Systems Interconnection protocols
Direct link-layer access
Point-to-Point Protocol
PARC Universal Packet protocol
Internal routing protocol
Simple Internet Protocol
IBM SNA protocol
UNIX sockets
Unspecified protocol, any supported address family
eXpress Transfer Protocol
Timestamp (bintime)
The sender’s credentials
Process credentials
Access rights
Timestamp (timeval)
Timestamp (timespec list) (Linux 2.6.30)
Timespec (timespec)
User credentials
Wifi status (Linux 3.3)
Shut down the reading side of the socket
Shut down the both sides of the socket
Shut down the writing side of the socket
A datagram socket provides connectionless, unreliable messaging
Device-level packet access
A raw socket provides low-level access for direct access or implementing network protocols
A reliable datagram socket provides reliable delivery of messages
A sequential packet socket provides sequenced, reliable two-way connection for datagrams
A stream socket provides a sequenced, reliable two-way connection for a byte stream
AppleTalk socket options
AX.25 socket options
IP socket options
IPX socket options
Socket-level options
TCP socket options
UDP socket options
Maximum connection requests that may be queued for a socket
Background socket priority
Interactive socket priority
Normal socket priority
Socket has had listen() called on it
There is an accept filter
Bypass zone boundaries
Attach an accept filter
Only send packets from the given interface
Receive timestamp with datagrams (bintime)
Query supported BPF extensions (Linux 3.14)
Permit sending of broadcast messages
Set the threshold in microseconds for low latency polling (Linux 3.11)
Debug info recording
Detach an accept filter
Domain given for socket() (Linux 2.6.32)
Use interface addresses
Retain unread data
Get and clear the error status
Obtain filter set by SO_ATTACH_FILTER (Linux 3.8)
Keep connections alive
Linger on close if data is present
Lock the filter attached to a socket (Linux 3.9)
Mandatory Access Control exemption for unlabeled peers
Set the mark for mark-based routing (Linux 2.6.25)
Cap the rate computed by transport layer. [bytes per second] (Linux 3.13)
Install socket-level Network Kernel Extension
Set netns of a socket (Linux 3.4)
Don’t SIGPIPE on EPIPE
Disable checksums
Get first packet byte count
Leave received out-of-band data in-line
Receive SCM_CREDENTIALS messages
Toggle security context passing (Linux 2.6.18)
Set the peek offset (Linux 3.4)
The credentials of the foreign process connected to this socket
Name of the connecting user
Obtain the security credentials (Linux 2.6.2)
The protocol-defined priority for all packets on this socket
Protocol given for socket() (Linux 2.6.32)
Receive buffer size
Receive buffer size without rmem_max limit (Linux 2.6.14)
Receive low-water mark
Receive timeout
Receive user credentials with datagram
Allow local address reuse
Allow local address and port reuse
Toggle cmsg for number of packets dropped (Linux 2.6.33)
Make select() detect socket error queue with errorfds (Linux 3.10)
Send buffer size
Send buffer size without wmem_max limit (Linux 2.6.14)
Send low-water mark
Send timeout
Receive timestamp with datagrams (timeval)
Time stamping of incoming and outgoing packets (Linux 2.6.30)
Receive nanosecond timestamp with datagrams (timespec)
Get the socket type
Bypass hardware when possible
Give a hint when more data is ready
OOB data is wanted in MSG_FLAG on receive
Toggle cmsg for wifi status (Linux 3.3)
TCP congestion control algorithm (Linux 2.6.13, glibc 2.6)
TCP Cookie Transactions (Linux 2.6.33, glibc 2.18)
Don’t send partial frames (Linux 2.2, glibc 2.2)
Don’t notify a listening socket until data is ready (Linux 2.4, glibc 2.2)
Reduce step of the handshake process (Linux 3.7, glibc 2.18)
Retrieve information about this socket (Linux 2.4, glibc 2.2)
Maximum number of keepalive probes allowed before dropping a connection (Linux 2.4, glibc 2.2)
Idle time before keepalive probes are sent (Linux 2.4, glibc 2.2)
Time between keepalive probes (Linux 2.4, glibc 2.2)
Lifetime of orphaned FIN_WAIT2 sockets (Linux 2.4, glibc 2.2)
Set maximum segment size
Use MD5 digests (RFC2385, Linux 2.6.20, glibc 2.7)
Don’t delay sending to coalesce packets
Don’t use TCP options
Don’t push the last block of write
Sequence of a queue for repair mode (Linux 3.5, glibc 2.18)
Enable quickack mode (Linux 2.4.4, glibc 2.3)
Repair mode (Linux 3.5, glibc 2.18)
Options for repair mode (Linux 3.5, glibc 2.18)
Queue for repair mode (Linux 3.5, glibc 2.18)
Number of SYN retransmits before a connection is dropped (Linux 2.4, glibc 2.2)
Duplicated acknowledgments handling for thin-streams (Linux 2.6.34, glibc 2.18)
Linear timeouts for thin-streams (Linux 2.6.34, glibc 2.18)
TCP timestamp (Linux 3.9, glibc 2.18)
Max timeout before a TCP connection is aborted (Linux 2.6.37, glibc 2.18)
Clamp the size of the advertised window (Linux 2.4, glibc 2.2)
Don’t send partial frames (Linux 2.5.44, glibc 2.11)
yield socket and client address for each a connection accepted via given sockets.
The arguments are a list of sockets. The individual argument should be a socket or an array of sockets.
This method yields the block sequentially. It means that the next connection is not accepted until the block returns. So concurrent mechanism, thread for example, should be used to service multiple clients at a time.
# File socket/lib/socket.rb, line 800 def self.accept_loop(*sockets) # :yield: socket, client_addrinfo sockets.flatten!(1) if sockets.empty? raise ArgumentError, "no sockets" end loop { readable, _, _ = IO.select(sockets) readable.each {|r| sock, addr = r.accept_nonblock(exception: false) next if sock == :wait_readable yield sock, addr } } end
Obtains address information for nodename:servname.
Note that Addrinfo.getaddrinfo provides the same functionality in an object oriented style.
family should be an address family such as: :INET, :INET6, etc.
socktype should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.
protocol should be a protocol defined in the family, and defaults to 0 for the family.
flags should be bitwise OR of Socket::AI_* constants.
Socket.getaddrinfo("www.ruby-lang.org", "http", nil, :STREAM) #=> [["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68", 2, 1, 6]] # PF_INET/SOCK_STREAM/IPPROTO_TCP Socket.getaddrinfo("localhost", nil) #=> [["AF_INET", 0, "localhost", "127.0.0.1", 2, 1, 6], # PF_INET/SOCK_STREAM/IPPROTO_TCP # ["AF_INET", 0, "localhost", "127.0.0.1", 2, 2, 17], # PF_INET/SOCK_DGRAM/IPPROTO_UDP # ["AF_INET", 0, "localhost", "127.0.0.1", 2, 3, 0]] # PF_INET/SOCK_RAW/IPPROTO_IP
reverse_lookup directs the form of the third element, and has to
be one of below. If reverse_lookup is omitted, the default value
is nil
.
+true+, +:hostname+: hostname is obtained from numeric address using reverse lookup, which may take a time. +false+, +:numeric+: hostname is same as numeric address. +nil+: obey to the current +do_not_reverse_lookup+ flag.
If Addrinfo object is preferred, use Addrinfo.getaddrinfo.
static VALUE sock_s_getaddrinfo(int argc, VALUE *argv, VALUE _) { VALUE host, port, family, socktype, protocol, flags, ret, revlookup; struct addrinfo hints; struct rb_addrinfo *res; int norevlookup; rb_scan_args(argc, argv, "25", &host, &port, &family, &socktype, &protocol, &flags, &revlookup); MEMZERO(&hints, struct addrinfo, 1); hints.ai_family = NIL_P(family) ? PF_UNSPEC : rsock_family_arg(family); if (!NIL_P(socktype)) { hints.ai_socktype = rsock_socktype_arg(socktype); } if (!NIL_P(protocol)) { hints.ai_protocol = NUM2INT(protocol); } if (!NIL_P(flags)) { hints.ai_flags = NUM2INT(flags); } if (NIL_P(revlookup) || !rsock_revlookup_flag(revlookup, &norevlookup)) { norevlookup = rsock_do_not_reverse_lookup; } res = rsock_getaddrinfo(host, port, &hints, 0); ret = make_addrinfo(res, norevlookup); rb_freeaddrinfo(res); return ret; }
Use Addrinfo#getnameinfo instead. This method is deprecated for the following reasons:
Uncommon address representation: 4/16-bytes binary string to represent IPv4/IPv6 address.
gethostbyaddr() may take a long time and it may block other threads. (GVL cannot be released since gethostbyname() is not thread safe.)
This method uses gethostbyname() function already removed from POSIX.
This method obtains the host information for address.
p Socket.gethostbyaddr([221,186,184,68].pack("CCCC")) #=> ["carbon.ruby-lang.org", [], 2, "\xDD\xBA\xB8D"] p Socket.gethostbyaddr([127,0,0,1].pack("CCCC")) ["localhost", [], 2, "\x7F\x00\x00\x01"] p Socket.gethostbyaddr(([0]*15+[1]).pack("C"*16)) #=> ["localhost", ["ip6-localhost", "ip6-loopback"], 10, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"]
static VALUE sock_s_gethostbyaddr(int argc, VALUE *argv, VALUE _) { VALUE addr, family; struct hostent *h; char **pch; VALUE ary, names; int t = AF_INET; rb_scan_args(argc, argv, "11", &addr, &family); StringValue(addr); if (!NIL_P(family)) { t = rsock_family_arg(family); } #ifdef AF_INET6 else if (RSTRING_LEN(addr) == 16) { t = AF_INET6; } #endif h = gethostbyaddr(RSTRING_PTR(addr), RSTRING_SOCKLEN(addr), t); if (h == NULL) { #ifdef HAVE_HSTRERROR extern int h_errno; rb_raise(rb_eSocket, "%s", (char*)hstrerror(h_errno)); #else rb_raise(rb_eSocket, "host not found"); #endif } ary = rb_ary_new(); rb_ary_push(ary, rb_str_new2(h->h_name)); names = rb_ary_new(); rb_ary_push(ary, names); if (h->h_aliases != NULL) { for (pch = h->h_aliases; *pch; pch++) { rb_ary_push(names, rb_str_new2(*pch)); } } rb_ary_push(ary, INT2NUM(h->h_addrtype)); #ifdef h_addr for (pch = h->h_addr_list; *pch; pch++) { rb_ary_push(ary, rb_str_new(*pch, h->h_length)); } #else rb_ary_push(ary, rb_str_new(h->h_addr, h->h_length)); #endif return ary; }
Use Addrinfo.getaddrinfo instead. This method is deprecated for the following reasons:
The 3rd element of the result is the address family of the first address. The address families of the rest of the addresses are not returned.
Uncommon address representation: 4/16-bytes binary string to represent IPv4/IPv6 address.
gethostbyname() may take a long time and it may block other threads. (GVL cannot be released since gethostbyname() is not thread safe.)
This method uses gethostbyname() function already removed from POSIX.
This method obtains the host information for hostname.
p Socket.gethostbyname("hal") #=> ["localhost", ["hal"], 2, "\x7F\x00\x00\x01"]
static VALUE sock_s_gethostbyname(VALUE obj, VALUE host) { struct rb_addrinfo *res = rsock_addrinfo(host, Qnil, AF_UNSPEC, SOCK_STREAM, AI_CANONNAME); return rsock_make_hostent(host, res, sock_sockaddr); }
Returns the hostname.
p Socket.gethostname #=> "hal"
Note that it is not guaranteed to be able to convert to IP address using gethostbyname, getaddrinfo, etc. If you need local IP address, use ::ip_address_list.
static VALUE sock_gethostname(VALUE obj) { #if defined(NI_MAXHOST) # define RUBY_MAX_HOST_NAME_LEN NI_MAXHOST #elif defined(HOST_NAME_MAX) # define RUBY_MAX_HOST_NAME_LEN HOST_NAME_MAX #else # define RUBY_MAX_HOST_NAME_LEN 1024 #endif long len = RUBY_MAX_HOST_NAME_LEN; VALUE name; name = rb_str_new(0, len); while (gethostname(RSTRING_PTR(name), len) < 0) { int e = errno; switch (e) { case ENAMETOOLONG: #ifdef __linux__ case EINVAL: /* glibc before version 2.1 uses EINVAL instead of ENAMETOOLONG */ #endif break; default: rb_syserr_fail(e, "gethostname(3)"); } rb_str_modify_expand(name, len); len += len; } rb_str_resize(name, strlen(RSTRING_PTR(name))); return name; }
Returns an array of interface addresses. An element of the array is an instance of Socket::Ifaddr.
This method can be used to find multicast-enabled interfaces:
pp Socket.getifaddrs.reject {|ifaddr| !ifaddr.addr.ip? || (ifaddr.flags & Socket::IFF_MULTICAST == 0) }.map {|ifaddr| [ifaddr.name, ifaddr.ifindex, ifaddr.addr] } #=> [["eth0", 2, #<Addrinfo: 221.186.184.67>], # ["eth0", 2, #<Addrinfo: fe80::216:3eff:fe95:88bb%eth0>]]
Example result on GNU/Linux:
pp Socket.getifaddrs #=> [#<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 PACKET[protocol=0 lo hatype=772 HOST hwaddr=00:00:00:00:00:00]>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 PACKET[protocol=0 eth0 hatype=1 HOST hwaddr=00:16:3e:95:88:bb] broadcast=PACKET[protocol=0 eth0 hatype=1 HOST hwaddr=ff:ff:ff:ff:ff:ff]>, # #<Socket::Ifaddr sit0 NOARP PACKET[protocol=0 sit0 hatype=776 HOST hwaddr=00:00:00:00]>, # #<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 127.0.0.1 netmask=255.0.0.0>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 221.186.184.67 netmask=255.255.255.240 broadcast=221.186.184.79>, # #<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 ::1 netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 fe80::216:3eff:fe95:88bb%eth0 netmask=ffff:ffff:ffff:ffff::>]
Example result on FreeBSD:
pp Socket.getifaddrs #=> [#<Socket::Ifaddr usbus0 UP,0x10000 LINK[usbus0]>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 LINK[re0 3a:d0:40:9a:fe:e8]>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 10.250.10.18 netmask=255.255.255.? (7 bytes for 16 bytes sockaddr_in) broadcast=10.250.10.255>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 fe80:2::38d0:40ff:fe9a:fee8 netmask=ffff:ffff:ffff:ffff::>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 2001:2e8:408:10::12 netmask=UNSPEC>, # #<Socket::Ifaddr plip0 POINTOPOINT,MULTICAST,0x800 LINK[plip0]>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST LINK[lo0]>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST ::1 netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST fe80:4::1 netmask=ffff:ffff:ffff:ffff::>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST 127.0.0.1 netmask=255.?.?.? (5 bytes for 16 bytes sockaddr_in)>]
static VALUE socket_s_getifaddrs(VALUE self) { return rsock_getifaddrs(); }
Obtains name information for sockaddr.
sockaddr should be one of follows.
packed sockaddr string such as ::sockaddr_in(80, “127.0.0.1”)
3-elements array such as [“AF_INET”, 80, “127.0.0.1”]
4-elements array such as [“AF_INET”, 80, ignored, “127.0.0.1”]
flags should be bitwise OR of Socket::NI_* constants.
Note: The last form is compatible with IPSocket#addr and IPSocket#peeraddr.
Socket.getnameinfo(Socket.sockaddr_in(80, "127.0.0.1")) #=> ["localhost", "www"] Socket.getnameinfo(["AF_INET", 80, "127.0.0.1"]) #=> ["localhost", "www"] Socket.getnameinfo(["AF_INET", 80, "localhost", "127.0.0.1"]) #=> ["localhost", "www"]
If Addrinfo object is preferred, use Addrinfo#getnameinfo.
static VALUE sock_s_getnameinfo(int argc, VALUE *argv, VALUE _) { VALUE sa, af = Qnil, host = Qnil, port = Qnil, flags, tmp; char *hptr, *pptr; char hbuf[1024], pbuf[1024]; int fl; struct rb_addrinfo *res = NULL; struct addrinfo hints, *r; int error, saved_errno; union_sockaddr ss; struct sockaddr *sap; socklen_t salen; sa = flags = Qnil; rb_scan_args(argc, argv, "11", &sa, &flags); fl = 0; if (!NIL_P(flags)) { fl = NUM2INT(flags); } tmp = rb_check_sockaddr_string_type(sa); if (!NIL_P(tmp)) { sa = tmp; if (sizeof(ss) < (size_t)RSTRING_LEN(sa)) { rb_raise(rb_eTypeError, "sockaddr length too big"); } memcpy(&ss, RSTRING_PTR(sa), RSTRING_LEN(sa)); if (!VALIDATE_SOCKLEN(&ss.addr, RSTRING_LEN(sa))) { rb_raise(rb_eTypeError, "sockaddr size differs - should not happen"); } sap = &ss.addr; salen = RSTRING_SOCKLEN(sa); goto call_nameinfo; } tmp = rb_check_array_type(sa); if (!NIL_P(tmp)) { sa = tmp; MEMZERO(&hints, struct addrinfo, 1); if (RARRAY_LEN(sa) == 3) { af = RARRAY_AREF(sa, 0); port = RARRAY_AREF(sa, 1); host = RARRAY_AREF(sa, 2); } else if (RARRAY_LEN(sa) >= 4) { af = RARRAY_AREF(sa, 0); port = RARRAY_AREF(sa, 1); host = RARRAY_AREF(sa, 3); if (NIL_P(host)) { host = RARRAY_AREF(sa, 2); } else { /* * 4th element holds numeric form, don't resolve. * see rsock_ipaddr(). */ #ifdef AI_NUMERICHOST /* AIX 4.3.3 doesn't have AI_NUMERICHOST. */ hints.ai_flags |= AI_NUMERICHOST; #endif } } else { rb_raise(rb_eArgError, "array size should be 3 or 4, %ld given", RARRAY_LEN(sa)); } /* host */ if (NIL_P(host)) { hptr = NULL; } else { strncpy(hbuf, StringValueCStr(host), sizeof(hbuf)); hbuf[sizeof(hbuf) - 1] = '\0'; hptr = hbuf; } /* port */ if (NIL_P(port)) { strcpy(pbuf, "0"); pptr = NULL; } else if (FIXNUM_P(port)) { snprintf(pbuf, sizeof(pbuf), "%ld", NUM2LONG(port)); pptr = pbuf; } else { strncpy(pbuf, StringValueCStr(port), sizeof(pbuf)); pbuf[sizeof(pbuf) - 1] = '\0'; pptr = pbuf; } hints.ai_socktype = (fl & NI_DGRAM) ? SOCK_DGRAM : SOCK_STREAM; /* af */ hints.ai_family = NIL_P(af) ? PF_UNSPEC : rsock_family_arg(af); error = rb_getaddrinfo(hptr, pptr, &hints, &res); if (error) goto error_exit_addr; sap = res->ai->ai_addr; salen = res->ai->ai_addrlen; } else { rb_raise(rb_eTypeError, "expecting String or Array"); } call_nameinfo: error = rb_getnameinfo(sap, salen, hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), fl); if (error) goto error_exit_name; if (res) { for (r = res->ai->ai_next; r; r = r->ai_next) { char hbuf2[1024], pbuf2[1024]; sap = r->ai_addr; salen = r->ai_addrlen; error = rb_getnameinfo(sap, salen, hbuf2, sizeof(hbuf2), pbuf2, sizeof(pbuf2), fl); if (error) goto error_exit_name; if (strcmp(hbuf, hbuf2) != 0|| strcmp(pbuf, pbuf2) != 0) { rb_freeaddrinfo(res); rb_raise(rb_eSocket, "sockaddr resolved to multiple nodename"); } } rb_freeaddrinfo(res); } return rb_assoc_new(rb_str_new2(hbuf), rb_str_new2(pbuf)); error_exit_addr: saved_errno = errno; if (res) rb_freeaddrinfo(res); errno = saved_errno; rsock_raise_socket_error("getaddrinfo", error); error_exit_name: saved_errno = errno; if (res) rb_freeaddrinfo(res); errno = saved_errno; rsock_raise_socket_error("getnameinfo", error); UNREACHABLE_RETURN(Qnil); }
Obtains the port number for service_name.
If protocol_name is not given, “tcp” is assumed.
Socket.getservbyname("smtp") #=> 25 Socket.getservbyname("shell") #=> 514 Socket.getservbyname("syslog", "udp") #=> 514
static VALUE sock_s_getservbyname(int argc, VALUE *argv, VALUE _) { VALUE service, proto; struct servent *sp; long port; const char *servicename, *protoname = "tcp"; rb_scan_args(argc, argv, "11", &service, &proto); StringValue(service); if (!NIL_P(proto)) StringValue(proto); servicename = StringValueCStr(service); if (!NIL_P(proto)) protoname = StringValueCStr(proto); sp = getservbyname(servicename, protoname); if (sp) { port = ntohs(sp->s_port); } else { char *end; port = STRTOUL(servicename, &end, 0); if (*end != '\0') { rb_raise(rb_eSocket, "no such service %s/%s", servicename, protoname); } } return INT2FIX(port); }
Obtains the port number for port.
If protocol_name is not given, “tcp” is assumed.
Socket.getservbyport(80) #=> "www" Socket.getservbyport(514, "tcp") #=> "shell" Socket.getservbyport(514, "udp") #=> "syslog"
static VALUE sock_s_getservbyport(int argc, VALUE *argv, VALUE _) { VALUE port, proto; struct servent *sp; long portnum; const char *protoname = "tcp"; rb_scan_args(argc, argv, "11", &port, &proto); portnum = NUM2LONG(port); if (portnum != (uint16_t)portnum) { const char *s = portnum > 0 ? "big" : "small"; rb_raise(rb_eRangeError, "integer %ld too %s to convert into `int16_t'", portnum, s); } if (!NIL_P(proto)) protoname = StringValueCStr(proto); sp = getservbyport((int)htons((uint16_t)portnum), protoname); if (!sp) { rb_raise(rb_eSocket, "no such service for port %d/%s", (int)portnum, protoname); } return rb_str_new2(sp->s_name); }
Returns local IP addresses as an array.
The array contains Addrinfo objects.
pp Socket.ip_address_list #=> [#<Addrinfo: 127.0.0.1>, #<Addrinfo: 192.168.0.128>, #<Addrinfo: ::1>, ...]
static VALUE socket_s_ip_address_list(VALUE self) { #if defined(HAVE_GETIFADDRS) struct ifaddrs *ifp = NULL; struct ifaddrs *p; int ret; VALUE list; ret = getifaddrs(&ifp); if (ret == -1) { rb_sys_fail("getifaddrs"); } list = rb_ary_new(); for (p = ifp; p; p = p->ifa_next) { if (p->ifa_addr != NULL && IS_IP_FAMILY(p->ifa_addr->sa_family)) { struct sockaddr *addr = p->ifa_addr; #if defined(AF_INET6) && defined(__sun) /* * OpenIndiana SunOS 5.11 getifaddrs() returns IPv6 link local * address with sin6_scope_id == 0. * So fill it from the interface name (ifa_name). */ struct sockaddr_in6 addr6; if (addr->sa_family == AF_INET6) { socklen_t len = (socklen_t)sizeof(struct sockaddr_in6); memcpy(&addr6, addr, len); addr = (struct sockaddr *)&addr6; if (IN6_IS_ADDR_LINKLOCAL(&addr6.sin6_addr) && addr6.sin6_scope_id == 0) { unsigned int ifindex = if_nametoindex(p->ifa_name); if (ifindex != 0) { addr6.sin6_scope_id = ifindex; } } } #endif rb_ary_push(list, sockaddr_obj(addr, sockaddr_len(addr))); } } freeifaddrs(ifp); return list; #elif defined(SIOCGLIFCONF) && defined(SIOCGLIFNUM) && !defined(__hpux) /* Solaris if_tcp(7P) */ /* HP-UX has SIOCGLIFCONF too. But it uses different struct */ int fd = -1; int ret; struct lifnum ln; struct lifconf lc; const char *reason = NULL; int save_errno; int i; VALUE list = Qnil; lc.lifc_buf = NULL; fd = socket(AF_INET, SOCK_DGRAM, 0); if (fd == -1) rb_sys_fail("socket(2)"); memset(&ln, 0, sizeof(ln)); ln.lifn_family = AF_UNSPEC; ret = ioctl(fd, SIOCGLIFNUM, &ln); if (ret == -1) { reason = "SIOCGLIFNUM"; goto finish; } memset(&lc, 0, sizeof(lc)); lc.lifc_family = AF_UNSPEC; lc.lifc_flags = 0; lc.lifc_len = sizeof(struct lifreq) * ln.lifn_count; lc.lifc_req = xmalloc(lc.lifc_len); ret = ioctl(fd, SIOCGLIFCONF, &lc); if (ret == -1) { reason = "SIOCGLIFCONF"; goto finish; } list = rb_ary_new(); for (i = 0; i < ln.lifn_count; i++) { struct lifreq *req = &lc.lifc_req[i]; if (IS_IP_FAMILY(req->lifr_addr.ss_family)) { if (req->lifr_addr.ss_family == AF_INET6 && IN6_IS_ADDR_LINKLOCAL(&((struct sockaddr_in6 *)(&req->lifr_addr))->sin6_addr) && ((struct sockaddr_in6 *)(&req->lifr_addr))->sin6_scope_id == 0) { struct lifreq req2; memcpy(req2.lifr_name, req->lifr_name, LIFNAMSIZ); ret = ioctl(fd, SIOCGLIFINDEX, &req2); if (ret == -1) { reason = "SIOCGLIFINDEX"; goto finish; } ((struct sockaddr_in6 *)(&req->lifr_addr))->sin6_scope_id = req2.lifr_index; } rb_ary_push(list, sockaddr_obj((struct sockaddr *)&req->lifr_addr, req->lifr_addrlen)); } } finish: save_errno = errno; if (lc.lifc_buf != NULL) xfree(lc.lifc_req); if (fd != -1) close(fd); errno = save_errno; if (reason) rb_syserr_fail(save_errno, reason); return list; #elif defined(SIOCGIFCONF) int fd = -1; int ret; #define EXTRA_SPACE ((int)(sizeof(struct ifconf) + sizeof(union_sockaddr))) char initbuf[4096+EXTRA_SPACE]; char *buf = initbuf; int bufsize; struct ifconf conf; struct ifreq *req; VALUE list = Qnil; const char *reason = NULL; int save_errno; fd = socket(AF_INET, SOCK_DGRAM, 0); if (fd == -1) rb_sys_fail("socket(2)"); bufsize = sizeof(initbuf); buf = initbuf; retry: conf.ifc_len = bufsize; conf.ifc_req = (struct ifreq *)buf; /* fprintf(stderr, "bufsize: %d\n", bufsize); */ ret = ioctl(fd, SIOCGIFCONF, &conf); if (ret == -1) { reason = "SIOCGIFCONF"; goto finish; } /* fprintf(stderr, "conf.ifc_len: %d\n", conf.ifc_len); */ if (bufsize - EXTRA_SPACE < conf.ifc_len) { if (bufsize < conf.ifc_len) { /* NetBSD returns required size for all interfaces. */ bufsize = conf.ifc_len + EXTRA_SPACE; } else { bufsize = bufsize << 1; } if (buf == initbuf) buf = NULL; buf = xrealloc(buf, bufsize); goto retry; } close(fd); fd = -1; list = rb_ary_new(); req = conf.ifc_req; while ((char*)req < (char*)conf.ifc_req + conf.ifc_len) { struct sockaddr *addr = &req->ifr_addr; if (IS_IP_FAMILY(addr->sa_family)) { rb_ary_push(list, sockaddr_obj(addr, sockaddr_len(addr))); } #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN # ifndef _SIZEOF_ADDR_IFREQ # define _SIZEOF_ADDR_IFREQ(r) \ (sizeof(struct ifreq) + \ (sizeof(struct sockaddr) < (r).ifr_addr.sa_len ? \ (r).ifr_addr.sa_len - sizeof(struct sockaddr) : \ 0)) # endif req = (struct ifreq *)((char*)req + _SIZEOF_ADDR_IFREQ(*req)); #else req = (struct ifreq *)((char*)req + sizeof(struct ifreq)); #endif } finish: save_errno = errno; if (buf != initbuf) xfree(buf); if (fd != -1) close(fd); errno = save_errno; if (reason) rb_syserr_fail(save_errno, reason); return list; #undef EXTRA_SPACE #elif defined(_WIN32) typedef struct ip_adapter_unicast_address_st { unsigned LONG_LONG dummy0; struct ip_adapter_unicast_address_st *Next; struct { struct sockaddr *lpSockaddr; int iSockaddrLength; } Address; int dummy1; int dummy2; int dummy3; long dummy4; long dummy5; long dummy6; } ip_adapter_unicast_address_t; typedef struct ip_adapter_anycast_address_st { unsigned LONG_LONG dummy0; struct ip_adapter_anycast_address_st *Next; struct { struct sockaddr *lpSockaddr; int iSockaddrLength; } Address; } ip_adapter_anycast_address_t; typedef struct ip_adapter_addresses_st { unsigned LONG_LONG dummy0; struct ip_adapter_addresses_st *Next; void *dummy1; ip_adapter_unicast_address_t *FirstUnicastAddress; ip_adapter_anycast_address_t *FirstAnycastAddress; void *dummy2; void *dummy3; void *dummy4; void *dummy5; void *dummy6; BYTE dummy7[8]; DWORD dummy8; DWORD dummy9; DWORD dummy10; DWORD IfType; int OperStatus; DWORD dummy12; DWORD dummy13[16]; void *dummy14; } ip_adapter_addresses_t; typedef ULONG (WINAPI *GetAdaptersAddresses_t)(ULONG, ULONG, PVOID, ip_adapter_addresses_t *, PULONG); HMODULE h; GetAdaptersAddresses_t pGetAdaptersAddresses; ULONG len; DWORD ret; ip_adapter_addresses_t *adapters; VALUE list; h = LoadLibrary("iphlpapi.dll"); if (!h) rb_notimplement(); pGetAdaptersAddresses = (GetAdaptersAddresses_t)GetProcAddress(h, "GetAdaptersAddresses"); if (!pGetAdaptersAddresses) { FreeLibrary(h); rb_notimplement(); } ret = pGetAdaptersAddresses(AF_UNSPEC, 0, NULL, NULL, &len); if (ret != ERROR_SUCCESS && ret != ERROR_BUFFER_OVERFLOW) { errno = rb_w32_map_errno(ret); FreeLibrary(h); rb_sys_fail("GetAdaptersAddresses"); } adapters = (ip_adapter_addresses_t *)ALLOCA_N(BYTE, len); ret = pGetAdaptersAddresses(AF_UNSPEC, 0, NULL, adapters, &len); if (ret != ERROR_SUCCESS) { errno = rb_w32_map_errno(ret); FreeLibrary(h); rb_sys_fail("GetAdaptersAddresses"); } list = rb_ary_new(); for (; adapters; adapters = adapters->Next) { ip_adapter_unicast_address_t *uni; ip_adapter_anycast_address_t *any; if (adapters->OperStatus != 1) /* 1 means IfOperStatusUp */ continue; for (uni = adapters->FirstUnicastAddress; uni; uni = uni->Next) { #ifndef INET6 if (uni->Address.lpSockaddr->sa_family == AF_INET) #else if (IS_IP_FAMILY(uni->Address.lpSockaddr->sa_family)) #endif rb_ary_push(list, sockaddr_obj(uni->Address.lpSockaddr, uni->Address.iSockaddrLength)); } for (any = adapters->FirstAnycastAddress; any; any = any->Next) { #ifndef INET6 if (any->Address.lpSockaddr->sa_family == AF_INET) #else if (IS_IP_FAMILY(any->Address.lpSockaddr->sa_family)) #endif rb_ary_push(list, sockaddr_obj(any->Address.lpSockaddr, any->Address.iSockaddrLength)); } } FreeLibrary(h); return list; #endif }
Creates a new socket object.
domain should be a communications domain such as: :INET, :INET6, :UNIX, etc.
socktype should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.
protocol is optional and should be a protocol defined in the domain. If protocol is not given, 0 is used internally.
Socket.new(:INET, :STREAM) # TCP socket Socket.new(:INET, :DGRAM) # UDP socket Socket.new(:UNIX, :STREAM) # UNIX stream socket Socket.new(:UNIX, :DGRAM) # UNIX datagram socket
static VALUE sock_initialize(int argc, VALUE *argv, VALUE sock) { VALUE domain, type, protocol; int fd; int d, t; rb_scan_args(argc, argv, "21", &domain, &type, &protocol); if (NIL_P(protocol)) protocol = INT2FIX(0); setup_domain_and_type(domain, &d, type, &t); fd = rsock_socket(d, t, NUM2INT(protocol)); if (fd < 0) rb_sys_fail("socket(2)"); return rsock_init_sock(sock, fd); }
Packs port and host as an AF_INET/AF_INET6 sockaddr string.
Socket.sockaddr_in(80, "127.0.0.1") #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" Socket.sockaddr_in(80, "::1") #=> "\n\x00\x00P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00"
static VALUE sock_s_pack_sockaddr_in(VALUE self, VALUE port, VALUE host) { struct rb_addrinfo *res = rsock_addrinfo(host, port, AF_UNSPEC, 0, 0); VALUE addr = rb_str_new((char*)res->ai->ai_addr, res->ai->ai_addrlen); rb_freeaddrinfo(res); return addr; }
Packs path as an AF_UNIX sockaddr string.
Socket.sockaddr_un("/tmp/sock") #=> "\x01\x00/tmp/sock\x00\x00..."
static VALUE sock_s_pack_sockaddr_un(VALUE self, VALUE path) { struct sockaddr_un sockaddr; VALUE addr; StringValue(path); INIT_SOCKADDR_UN(&sockaddr, sizeof(struct sockaddr_un)); if (sizeof(sockaddr.sun_path) < (size_t)RSTRING_LEN(path)) { rb_raise(rb_eArgError, "too long unix socket path (%"PRIuSIZE" bytes given but %"PRIuSIZE" bytes max)", (size_t)RSTRING_LEN(path), sizeof(sockaddr.sun_path)); } memcpy(sockaddr.sun_path, RSTRING_PTR(path), RSTRING_LEN(path)); addr = rb_str_new((char*)&sockaddr, rsock_unix_sockaddr_len(path)); return addr; }
Creates a pair of sockets connected each other.
domain should be a communications domain such as: :INET, :INET6, :UNIX, etc.
socktype should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.
protocol should be a protocol defined in the domain, defaults to 0 for the domain.
s1, s2 = Socket.pair(:UNIX, :STREAM, 0) s1.send "a", 0 s1.send "b", 0 s1.close p s2.recv(10) #=> "ab" p s2.recv(10) #=> "" p s2.recv(10) #=> "" s1, s2 = Socket.pair(:UNIX, :DGRAM, 0) s1.send "a", 0 s1.send "b", 0 p s2.recv(10) #=> "a" p s2.recv(10) #=> "b"
VALUE rsock_sock_s_socketpair(int argc, VALUE *argv, VALUE klass) { VALUE domain, type, protocol; int d, t, p, sp[2]; int ret; VALUE s1, s2, r; rb_scan_args(argc, argv, "21", &domain, &type, &protocol); if (NIL_P(protocol)) protocol = INT2FIX(0); setup_domain_and_type(domain, &d, type, &t); p = NUM2INT(protocol); ret = rsock_socketpair(d, t, p, sp); if (ret < 0) { rb_sys_fail("socketpair(2)"); } s1 = rsock_init_sock(rb_obj_alloc(klass), sp[0]); s2 = rsock_init_sock(rb_obj_alloc(klass), sp[1]); r = rb_assoc_new(s1, s2); if (rb_block_given_p()) { return rb_ensure(pair_yield, r, io_close, s1); } return r; }
Packs port and host as an AF_INET/AF_INET6 sockaddr string.
Socket.sockaddr_in(80, "127.0.0.1") #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" Socket.sockaddr_in(80, "::1") #=> "\n\x00\x00P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00"
static VALUE sock_s_pack_sockaddr_in(VALUE self, VALUE port, VALUE host) { struct rb_addrinfo *res = rsock_addrinfo(host, port, AF_UNSPEC, 0, 0); VALUE addr = rb_str_new((char*)res->ai->ai_addr, res->ai->ai_addrlen); rb_freeaddrinfo(res); return addr; }
Packs path as an AF_UNIX sockaddr string.
Socket.sockaddr_un("/tmp/sock") #=> "\x01\x00/tmp/sock\x00\x00..."
static VALUE sock_s_pack_sockaddr_un(VALUE self, VALUE path) { struct sockaddr_un sockaddr; VALUE addr; StringValue(path); INIT_SOCKADDR_UN(&sockaddr, sizeof(struct sockaddr_un)); if (sizeof(sockaddr.sun_path) < (size_t)RSTRING_LEN(path)) { rb_raise(rb_eArgError, "too long unix socket path (%"PRIuSIZE" bytes given but %"PRIuSIZE" bytes max)", (size_t)RSTRING_LEN(path), sizeof(sockaddr.sun_path)); } memcpy(sockaddr.sun_path, RSTRING_PTR(path), RSTRING_LEN(path)); addr = rb_str_new((char*)&sockaddr, rsock_unix_sockaddr_len(path)); return addr; }
Creates a pair of sockets connected each other.
domain should be a communications domain such as: :INET, :INET6, :UNIX, etc.
socktype should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.
protocol should be a protocol defined in the domain, defaults to 0 for the domain.
s1, s2 = Socket.pair(:UNIX, :STREAM, 0) s1.send "a", 0 s1.send "b", 0 s1.close p s2.recv(10) #=> "ab" p s2.recv(10) #=> "" p s2.recv(10) #=> "" s1, s2 = Socket.pair(:UNIX, :DGRAM, 0) s1.send "a", 0 s1.send "b", 0 p s2.recv(10) #=> "a" p s2.recv(10) #=> "b"
VALUE rsock_sock_s_socketpair(int argc, VALUE *argv, VALUE klass) { VALUE domain, type, protocol; int d, t, p, sp[2]; int ret; VALUE s1, s2, r; rb_scan_args(argc, argv, "21", &domain, &type, &protocol); if (NIL_P(protocol)) protocol = INT2FIX(0); setup_domain_and_type(domain, &d, type, &t); p = NUM2INT(protocol); ret = rsock_socketpair(d, t, p, sp); if (ret < 0) { rb_sys_fail("socketpair(2)"); } s1 = rsock_init_sock(rb_obj_alloc(klass), sp[0]); s2 = rsock_init_sock(rb_obj_alloc(klass), sp[1]); r = rb_assoc_new(s1, s2); if (rb_block_given_p()) { return rb_ensure(pair_yield, r, io_close, s1); } return r; }
creates a new socket object connected to host:port using TCP/IP.
If local_host:local_port is given, the socket is bound to it.
The optional last argument opts is options represented by a hash. opts may have following options:
specify the timeout in seconds.
specify the name resolution timeout in seconds.
If a block is given, the block is called with the socket. The value of the block is returned. The socket is closed when this method returns.
If no block is given, the socket is returned.
Socket.tcp("www.ruby-lang.org", 80) {|sock| sock.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" sock.close_write puts sock.read }
# File socket/lib/socket.rb, line 623 def self.tcp(host, port, local_host = nil, local_port = nil, connect_timeout: nil, resolv_timeout: nil) # :yield: socket last_error = nil ret = nil local_addr_list = nil if local_host != nil || local_port != nil local_addr_list = Addrinfo.getaddrinfo(local_host, local_port, nil, :STREAM, nil) end Addrinfo.foreach(host, port, nil, :STREAM, timeout: resolv_timeout) {|ai| if local_addr_list local_addr = local_addr_list.find {|local_ai| local_ai.afamily == ai.afamily } next unless local_addr else local_addr = nil end begin sock = local_addr ? ai.connect_from(local_addr, timeout: connect_timeout) : ai.connect(timeout: connect_timeout) rescue SystemCallError last_error = $! next end ret = sock break } unless ret if last_error raise last_error else raise SocketError, "no appropriate local address" end end if block_given? begin yield ret ensure ret.close end else ret end end
creates a TCP/IP server on port and calls the block for each connection accepted. The block is called with a socket and a client_address as an Addrinfo object.
If host is specified, it is used with port to determine the server addresses.
The socket is not closed when the block returns. So application should close it explicitly.
This method calls the block sequentially. It means that the next connection is not accepted until the block returns. So concurrent mechanism, thread for example, should be used to service multiple clients at a time.
Note that Addrinfo.getaddrinfo is used to determine the server socket addresses. When Addrinfo.getaddrinfo returns two or more addresses, IPv4 and IPv6 address for example, all of them are used. ::tcp_server_loop succeeds if one socket can be used at least.
# Sequential echo server. # It services only one client at a time. Socket.tcp_server_loop(16807) {|sock, client_addrinfo| begin IO.copy_stream(sock, sock) ensure sock.close end } # Threaded echo server # It services multiple clients at a time. # Note that it may accept connections too much. Socket.tcp_server_loop(16807) {|sock, client_addrinfo| Thread.new { begin IO.copy_stream(sock, sock) ensure sock.close end } }
# File socket/lib/socket.rb, line 856 def self.tcp_server_loop(host=nil, port, &b) # :yield: socket, client_addrinfo tcp_server_sockets(host, port) {|sockets| accept_loop(sockets, &b) } end
creates TCP/IP server sockets for host and port. host is optional.
If no block given, it returns an array of listening sockets.
If a block is given, the block is called with the sockets. The value of the block is returned. The socket is closed when this method returns.
If port is 0, actual port number is chosen dynamically. However all sockets in the result has same port number.
# tcp_server_sockets returns two sockets. sockets = Socket.tcp_server_sockets(1296) p sockets #=> [#<Socket:fd 3>, #<Socket:fd 4>] # The sockets contains IPv6 and IPv4 sockets. sockets.each {|s| p s.local_address } #=> #<Addrinfo: [::]:1296 TCP> # #<Addrinfo: 0.0.0.0:1296 TCP> # IPv6 and IPv4 socket has same port number, 53114, even if it is chosen dynamically. sockets = Socket.tcp_server_sockets(0) sockets.each {|s| p s.local_address } #=> #<Addrinfo: [::]:53114 TCP> # #<Addrinfo: 0.0.0.0:53114 TCP> # The block is called with the sockets. Socket.tcp_server_sockets(0) {|sockets| p sockets #=> [#<Socket:fd 3>, #<Socket:fd 4>] }
# File socket/lib/socket.rb, line 756 def self.tcp_server_sockets(host=nil, port) if port == 0 sockets = tcp_server_sockets_port0(host) else last_error = nil sockets = [] begin Addrinfo.foreach(host, port, nil, :STREAM, nil, Socket::AI_PASSIVE) {|ai| begin s = ai.listen rescue SystemCallError last_error = $! next end sockets << s } if sockets.empty? raise last_error end rescue Exception sockets.each(&:close) raise end end if block_given? begin yield sockets ensure sockets.each(&:close) end else sockets end end
creates a UDP/IP server on port and calls the block for each message arrived. The block is called with the message and its source information.
This method allocates sockets internally using port. If host is specified, it is used conjunction with port to determine the server addresses.
The msg is a string.
The msg_src is a Socket::UDPSource object. It is used for reply.
# UDP/IP echo server. Socket.udp_server_loop(9261) {|msg, msg_src| msg_src.reply msg }
# File socket/lib/socket.rb, line 1026 def self.udp_server_loop(host=nil, port, &b) # :yield: message, message_source udp_server_sockets(host, port) {|sockets| udp_server_loop_on(sockets, &b) } end
Run UDP/IP server loop on the given sockets.
The return value of ::udp_server_sockets is appropriate for the argument.
It calls the block for each message received.
# File socket/lib/socket.rb, line 999 def self.udp_server_loop_on(sockets, &b) # :yield: msg, msg_src loop { readable, _, _ = IO.select(sockets) udp_server_recv(readable, &b) } end
Receive UDP/IP packets from the given sockets. For each packet received, the block is called.
The block receives msg and msg_src. msg is a string which is the payload of the received packet. msg_src is a Socket::UDPSource object which is used for reply.
::udp_server_loop can be implemented using this method as follows.
udp_server_sockets(host, port) {|sockets| loop { readable, _, _ = IO.select(sockets) udp_server_recv(readable) {|msg, msg_src| ... } } }
# File socket/lib/socket.rb, line 972 def self.udp_server_recv(sockets) sockets.each {|r| msg, sender_addrinfo, _, *controls = r.recvmsg_nonblock(exception: false) next if msg == :wait_readable ai = r.local_address if ai.ipv6? and pktinfo = controls.find {|c| c.cmsg_is?(:IPV6, :PKTINFO) } ai = Addrinfo.udp(pktinfo.ipv6_pktinfo_addr.ip_address, ai.ip_port) yield msg, UDPSource.new(sender_addrinfo, ai) {|reply_msg| r.sendmsg reply_msg, 0, sender_addrinfo, pktinfo } else yield msg, UDPSource.new(sender_addrinfo, ai) {|reply_msg| r.send reply_msg, 0, sender_addrinfo } end } end
Creates UDP/IP sockets for a UDP server.
If no block given, it returns an array of sockets.
If a block is given, the block is called with the sockets. The value of the block is returned. The sockets are closed when this method returns.
If port is zero, some port is chosen. But the chosen port is used for the all sockets.
# UDP/IP echo server Socket.udp_server_sockets(0) {|sockets| p sockets.first.local_address.ip_port #=> 32963 Socket.udp_server_loop_on(sockets) {|msg, msg_src| msg_src.reply msg } }
# File socket/lib/socket.rb, line 884 def self.udp_server_sockets(host=nil, port) last_error = nil sockets = [] ipv6_recvpktinfo = nil if defined? Socket::AncillaryData if defined? Socket::IPV6_RECVPKTINFO # RFC 3542 ipv6_recvpktinfo = Socket::IPV6_RECVPKTINFO elsif defined? Socket::IPV6_PKTINFO # RFC 2292 ipv6_recvpktinfo = Socket::IPV6_PKTINFO end end local_addrs = Socket.ip_address_list ip_list = [] Addrinfo.foreach(host, port, nil, :DGRAM, nil, Socket::AI_PASSIVE) {|ai| if ai.ipv4? && ai.ip_address == "0.0.0.0" local_addrs.each {|a| next unless a.ipv4? ip_list << Addrinfo.new(a.to_sockaddr, :INET, :DGRAM, 0); } elsif ai.ipv6? && ai.ip_address == "::" && !ipv6_recvpktinfo local_addrs.each {|a| next unless a.ipv6? ip_list << Addrinfo.new(a.to_sockaddr, :INET6, :DGRAM, 0); } else ip_list << ai end } ip_list.uniq!(&:to_sockaddr) if port == 0 sockets = ip_sockets_port0(ip_list, false) else ip_list.each {|ip| ai = Addrinfo.udp(ip.ip_address, port) begin s = ai.bind rescue SystemCallError last_error = $! next end sockets << s } if sockets.empty? raise last_error end end sockets.each {|s| ai = s.local_address if ipv6_recvpktinfo && ai.ipv6? && ai.ip_address == "::" s.setsockopt(:IPV6, ipv6_recvpktinfo, 1) end } if block_given? begin yield sockets ensure sockets.each(&:close) if sockets end else sockets end end
creates a new socket connected to path using UNIX socket socket.
If a block is given, the block is called with the socket. The value of the block is returned. The socket is closed when this method returns.
If no block is given, the socket is returned.
# talk to /tmp/sock socket. Socket.unix("/tmp/sock") {|sock| t = Thread.new { IO.copy_stream(sock, STDOUT) } IO.copy_stream(STDIN, sock) t.join }
# File socket/lib/socket.rb, line 1076 def self.unix(path) # :yield: socket addr = Addrinfo.unix(path) sock = addr.connect if block_given? begin yield sock ensure sock.close end else sock end end
creates a UNIX socket server on path. It calls the block for each socket accepted.
If host is specified, it is used with port to determine the server ports.
The socket is not closed when the block returns. So application should close it.
This method deletes the socket file pointed by path at first if the file is a socket file and it is owned by the user of the application. This is safe only if the directory of path is not changed by a malicious user. So don’t use /tmp/malicious-users-directory/socket. Note that /tmp/socket and /tmp/your-private-directory/socket is safe assuming that /tmp has sticky bit.
# Sequential echo server. # It services only one client at a time. Socket.unix_server_loop("/tmp/sock") {|sock, client_addrinfo| begin IO.copy_stream(sock, sock) ensure sock.close end }
# File socket/lib/socket.rb, line 1163 def self.unix_server_loop(path, &b) # :yield: socket, client_addrinfo unix_server_socket(path) {|serv| accept_loop(serv, &b) } end
creates a UNIX server socket on path
If no block given, it returns a listening socket.
If a block is given, it is called with the socket and the block value is returned. When the block exits, the socket is closed and the socket file is removed.
socket = Socket.unix_server_socket("/tmp/s") p socket #=> #<Socket:fd 3> p socket.local_address #=> #<Addrinfo: /tmp/s SOCK_STREAM> Socket.unix_server_socket("/tmp/sock") {|s| p s #=> #<Socket:fd 3> p s.local_address #=> # #<Addrinfo: /tmp/sock SOCK_STREAM> }
# File socket/lib/socket.rb, line 1106 def self.unix_server_socket(path) unless unix_socket_abstract_name?(path) begin st = File.lstat(path) rescue Errno::ENOENT end if st&.socket? && st.owned? File.unlink path end end s = Addrinfo.unix(path).listen if block_given? begin yield s ensure s.close unless unix_socket_abstract_name?(path) File.unlink path end end else s end end
Unpacks sockaddr into port and ip_address.
sockaddr should be a string or an addrinfo for AF_INET/AF_INET6.
sockaddr = Socket.sockaddr_in(80, "127.0.0.1") p sockaddr #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" p Socket.unpack_sockaddr_in(sockaddr) #=> [80, "127.0.0.1"]
static VALUE sock_s_unpack_sockaddr_in(VALUE self, VALUE addr) { struct sockaddr_in * sockaddr; VALUE host; sockaddr = (struct sockaddr_in*)SockAddrStringValuePtr(addr); if (RSTRING_LEN(addr) < (char*)&((struct sockaddr *)sockaddr)->sa_family + sizeof(((struct sockaddr *)sockaddr)->sa_family) - (char*)sockaddr) rb_raise(rb_eArgError, "too short sockaddr"); if (((struct sockaddr *)sockaddr)->sa_family != AF_INET #ifdef INET6 && ((struct sockaddr *)sockaddr)->sa_family != AF_INET6 #endif ) { #ifdef INET6 rb_raise(rb_eArgError, "not an AF_INET/AF_INET6 sockaddr"); #else rb_raise(rb_eArgError, "not an AF_INET sockaddr"); #endif } host = rsock_make_ipaddr((struct sockaddr*)sockaddr, RSTRING_SOCKLEN(addr)); return rb_assoc_new(INT2NUM(ntohs(sockaddr->sin_port)), host); }
Unpacks sockaddr into path.
sockaddr should be a string or an addrinfo for AF_UNIX.
sockaddr = Socket.sockaddr_un("/tmp/sock") p Socket.unpack_sockaddr_un(sockaddr) #=> "/tmp/sock"
static VALUE sock_s_unpack_sockaddr_un(VALUE self, VALUE addr) { struct sockaddr_un * sockaddr; VALUE path; sockaddr = (struct sockaddr_un*)SockAddrStringValuePtr(addr); if (RSTRING_LEN(addr) < (char*)&((struct sockaddr *)sockaddr)->sa_family + sizeof(((struct sockaddr *)sockaddr)->sa_family) - (char*)sockaddr) rb_raise(rb_eArgError, "too short sockaddr"); if (((struct sockaddr *)sockaddr)->sa_family != AF_UNIX) { rb_raise(rb_eArgError, "not an AF_UNIX sockaddr"); } if (sizeof(struct sockaddr_un) < (size_t)RSTRING_LEN(addr)) { rb_raise(rb_eTypeError, "too long sockaddr_un - %ld longer than %d", RSTRING_LEN(addr), (int)sizeof(struct sockaddr_un)); } path = rsock_unixpath_str(sockaddr, RSTRING_SOCKLEN(addr)); return path; }
Accepts a next connection. Returns a new Socket object and Addrinfo object.
serv = Socket.new(:INET, :STREAM, 0) serv.listen(5) c = Socket.new(:INET, :STREAM, 0) c.connect(serv.connect_address) p serv.accept #=> [#<Socket:fd 6>, #<Addrinfo: 127.0.0.1:48555 TCP>]
static VALUE sock_accept(VALUE sock) { rb_io_t *fptr; VALUE sock2; union_sockaddr buf; socklen_t len = (socklen_t)sizeof buf; GetOpenFile(sock, fptr); sock2 = rsock_s_accept(rb_cSocket,fptr->fd,&buf.addr,&len); return rb_assoc_new(sock2, rsock_io_socket_addrinfo(sock2, &buf.addr, len)); }
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an array containing the accepted socket for the incoming connection, client_socket, and an Addrinfo, client_addrinfo.
# In one script, start this first require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.bind(sockaddr) socket.listen(5) begin # emulate blocking accept client_socket, client_addrinfo = socket.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([socket]) retry end puts "The client said, '#{client_socket.readline.chomp}'" client_socket.puts "Hello from script one!" socket.close # In another script, start this second require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.connect(sockaddr) socket.puts "Hello from script 2." puts "The server said, '#{socket.readline.chomp}'" socket.close
Refer to #accept for the exceptions that may be thrown if the call to accept_nonblock fails.
#accept_nonblock may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
By specifying a keyword argument exception to false
,
you can indicate that #accept_nonblock should not
raise an IO::WaitReadable exception, but return the symbol
:wait_readable
instead.
# File socket/lib/socket.rb, line 592 def accept_nonblock(exception: true) __accept_nonblock(exception) end
Binds to the given local address.
local_sockaddr
- the struct
sockaddr contained in
a string or an Addrinfo object
require 'socket' # use Addrinfo socket = Socket.new(:INET, :STREAM, 0) socket.bind(Addrinfo.tcp("127.0.0.1", 2222)) p socket.local_address #=> #<Addrinfo: 127.0.0.1:2222 TCP> # use struct sockaddr include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' ) socket.bind( sockaddr )
On unix-based based systems the following system exceptions may be raised if the call to bind fails:
Errno::EACCES - the specified sockaddr is protected and the current user does not have permission to bind to it
Errno::EADDRINUSE - the specified sockaddr is already in use
Errno::EADDRNOTAVAIL - the specified sockaddr is not available from the local machine
Errno::EAFNOSUPPORT - the specified sockaddr is not a valid
address for the family of the calling socket
Errno::EBADF - the sockaddr specified is not a valid file descriptor
Errno::EFAULT - the sockaddr argument cannot be accessed
Errno::EINVAL - the socket
is already bound to an address, and
the protocol does not support binding to the new sockaddr or the
socket
has been shut down.
Errno::EINVAL - the address length is not a valid length for the address family
Errno::ENAMETOOLONG - the pathname resolved had a length which exceeded PATH_MAX
Errno::ENOBUFS - no buffer space is available
Errno::ENOSR - there were insufficient STREAMS resources available to complete the operation
Errno::ENOTSOCK - the socket
does not refer to a socket
Errno::EOPNOTSUPP - the socket type of the socket
does not
support binding to an address
On unix-based based systems if the address family of the calling
socket
is Socket::AF_UNIX the follow exceptions may be raised
if the call to bind fails:
Errno::EACCES - search permission is denied for a component of the prefix
path or write access to the socket
is denied
Errno::EDESTADDRREQ - the sockaddr argument is a null pointer
Errno::EISDIR - same as Errno::EDESTADDRREQ
Errno::EIO - an i/o error occurred
Errno::ELOOP - too many symbolic links were encountered in translating the pathname in sockaddr
Errno::ENAMETOOLLONG - a component of a pathname exceeded NAME_MAX characters, or an entire pathname exceeded PATH_MAX characters
Errno::ENOENT - a component of the pathname does not name an existing file or the pathname is an empty string
Errno::ENOTDIR - a component of the path prefix of the pathname in sockaddr is not a directory
Errno::EROFS - the name would reside on a read only filesystem
On Windows systems the following system exceptions may be raised if the call to bind fails:
Errno::ENETDOWN– the network is down
Errno::EACCES - the attempt to connect the datagram socket to the broadcast address failed
Errno::EADDRINUSE - the socket’s local address is already in use
Errno::EADDRNOTAVAIL - the specified address is not a valid address for this computer
Errno::EFAULT - the socket’s internal address or address length parameter is too small or is not a valid part of the user space addressed
Errno::EINVAL - the socket
is already bound to an address
Errno::ENOBUFS - no buffer space is available
Errno::ENOTSOCK - the socket
argument does not refer to a
socket
bind manual pages on unix-based systems
bind function in Microsoft’s Winsock functions reference
static VALUE sock_bind(VALUE sock, VALUE addr) { VALUE rai; rb_io_t *fptr; SockAddrStringValueWithAddrinfo(addr, rai); GetOpenFile(sock, fptr); if (bind(fptr->fd, (struct sockaddr*)RSTRING_PTR(addr), RSTRING_SOCKLEN(addr)) < 0) rsock_sys_fail_raddrinfo_or_sockaddr("bind(2)", addr, rai); return INT2FIX(0); }
Requests a connection to be made on the given remote_sockaddr
.
Returns 0 if successful, otherwise an exception is raised.
remote_sockaddr
- the struct
sockaddr contained
in a string or Addrinfo object
# Pull down Google's web page require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 80, 'www.google.com' ) socket.connect( sockaddr ) socket.write( "GET / HTTP/1.0\r\n\r\n" ) results = socket.read
On unix-based systems the following system exceptions may be raised if the call to connect fails:
Errno::EACCES - search permission is denied for a component of the prefix
path or write access to the socket
is denied
Errno::EADDRINUSE - the sockaddr is already in use
Errno::EADDRNOTAVAIL - the specified sockaddr is not available from the local machine
Errno::EAFNOSUPPORT - the specified sockaddr is not a valid
address for the address family of the specified socket
Errno::EALREADY - a connection is already in progress for the specified socket
Errno::EBADF - the socket
is not a valid file descriptor
Errno::ECONNREFUSED - the target sockaddr was not listening for connections refused the connection request
Errno::ECONNRESET - the remote host reset the connection request
Errno::EFAULT - the sockaddr cannot be accessed
Errno::EHOSTUNREACH - the destination host cannot be reached (probably because the host is down or a remote router cannot reach it)
Errno::EINPROGRESS - the O_NONBLOCK is set for the socket
and
the connection cannot be immediately established; the connection will be
established asynchronously
Errno::EINTR - the attempt to establish the connection was interrupted by delivery of a signal that was caught; the connection will be established asynchronously
Errno::EISCONN - the specified socket
is already connected
Errno::EINVAL - the address length used for the sockaddr is not a valid length for the address family or there is an invalid family in sockaddr
Errno::ENAMETOOLONG - the pathname resolved had a length which exceeded PATH_MAX
Errno::ENETDOWN - the local interface used to reach the destination is down
Errno::ENETUNREACH - no route to the network is present
Errno::ENOBUFS - no buffer space is available
Errno::ENOSR - there were insufficient STREAMS resources available to complete the operation
Errno::ENOTSOCK - the socket
argument does not refer to a
socket
Errno::EOPNOTSUPP - the calling socket
is listening and cannot
be connected
Errno::EPROTOTYPE - the sockaddr has a different type than the socket bound to the specified peer address
Errno::ETIMEDOUT - the attempt to connect time out before a connection was made.
On unix-based systems if the address family of the calling
socket
is AF_UNIX the follow
exceptions may be raised if the call to connect fails:
Errno::EIO - an i/o error occurred while reading from or writing to the file system
Errno::ELOOP - too many symbolic links were encountered in translating the pathname in sockaddr
Errno::ENAMETOOLLONG - a component of a pathname exceeded NAME_MAX characters, or an entire pathname exceeded PATH_MAX characters
Errno::ENOENT - a component of the pathname does not name an existing file or the pathname is an empty string
Errno::ENOTDIR - a component of the path prefix of the pathname in sockaddr is not a directory
On Windows systems the following system exceptions may be raised if the call to connect fails:
Errno::ENETDOWN - the network is down
Errno::EADDRINUSE - the socket’s local address is already in use
Errno::EINTR - the socket was cancelled
Errno::EINPROGRESS - a blocking socket is in progress or the service
provider is still processing a callback function. Or a nonblocking connect
call is in progress on the socket
.
Errno::EALREADY - see Errno::EINVAL
Errno::EADDRNOTAVAIL - the remote address is not a valid address, such as ADDR_ANY TODO check ADDRANY TO INADDR_ANY
Errno::EAFNOSUPPORT - addresses in the specified family cannot be used with
with this socket
Errno::ECONNREFUSED - the target sockaddr was not listening for connections refused the connection request
Errno::EFAULT - the socket’s internal address or address length parameter is too small or is not a valid part of the user space address
Errno::EINVAL - the socket
is a listening socket
Errno::EISCONN - the socket
is already connected
Errno::ENETUNREACH - the network cannot be reached from this host at this time
Errno::EHOSTUNREACH - no route to the network is present
Errno::ENOBUFS - no buffer space is available
Errno::ENOTSOCK - the socket
argument does not refer to a
socket
Errno::ETIMEDOUT - the attempt to connect time out before a connection was made.
Errno::EWOULDBLOCK - the socket is marked as nonblocking and the connection cannot be completed immediately
Errno::EACCES - the attempt to connect the datagram socket to the broadcast address failed
connect manual pages on unix-based systems
connect function in Microsoft’s Winsock functions reference
static VALUE sock_connect(VALUE sock, VALUE addr) { VALUE rai; rb_io_t *fptr; int fd, n; SockAddrStringValueWithAddrinfo(addr, rai); addr = rb_str_new4(addr); GetOpenFile(sock, fptr); fd = fptr->fd; n = rsock_connect(fd, (struct sockaddr*)RSTRING_PTR(addr), RSTRING_SOCKLEN(addr), 0); if (n < 0) { rsock_sys_fail_raddrinfo_or_sockaddr("connect(2)", addr, rai); } return INT2FIX(n); }
Requests a connection to be made on the given remote_sockaddr
after O_NONBLOCK is set for the underlying file descriptor. Returns 0 if
successful, otherwise an exception is raised.
# +remote_sockaddr+ - the +struct+ sockaddr contained in a string or Addrinfo object
# Pull down Google's web page require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(80, 'www.google.com') begin # emulate blocking connect socket.connect_nonblock(sockaddr) rescue IO::WaitWritable IO.select(nil, [socket]) # wait 3-way handshake completion begin socket.connect_nonblock(sockaddr) # check connection failure rescue Errno::EISCONN end end socket.write("GET / HTTP/1.0\r\n\r\n") results = socket.read
Refer to #connect for the exceptions that may be thrown if the call to connect_nonblock fails.
#connect_nonblock may raise any error corresponding to connect(2) failure, including Errno::EINPROGRESS.
If the exception is Errno::EINPROGRESS, it is extended by IO::WaitWritable. So IO::WaitWritable can be used to rescue the exceptions for retrying connect_nonblock.
By specifying a keyword argument exception to false
,
you can indicate that #connect_nonblock should
not raise an IO::WaitWritable exception, but return the symbol
:wait_writable
instead.
# Socket#connect
# File socket/lib/socket.rb, line 1213 def connect_nonblock(addr, exception: true) __connect_nonblock(addr, exception) end
enable the socket option IPV6_V6ONLY if IPV6_V6ONLY is available.
# File socket/lib/socket.rb, line 463 def ipv6only! if defined? Socket::IPV6_V6ONLY self.setsockopt(:IPV6, :V6ONLY, 1) end end
Listens for connections, using the specified int
as the
backlog. A call to listen only applies if the socket
is of type SOCK_STREAM or SOCK_SEQPACKET.
backlog
- the maximum length of the queue for pending
connections.
require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' ) socket.bind( sockaddr ) socket.listen( 5 )
require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) socket.listen( 1 )
On unix based systems the above will work because a new
sockaddr
struct is created on the address ADDR_ANY, for an
arbitrary port number as handed off by the kernel. It will not work on
Windows, because Windows requires that the socket
is bound by
calling bind before it can listen.
If the backlog amount exceeds the implementation-dependent maximum queue length, the implementation’s maximum queue length will be used.
On unix-based based systems the following system exceptions may be raised if the call to listen fails:
Errno::EBADF - the socket argument is not a valid file descriptor
Errno::EDESTADDRREQ - the socket is not bound to a local address, and the protocol does not support listening on an unbound socket
Errno::EINVAL - the socket is already connected
Errno::ENOTSOCK - the socket argument does not refer to a socket
Errno::EOPNOTSUPP - the socket protocol does not support listen
Errno::EACCES - the calling process does not have appropriate privileges
Errno::EINVAL - the socket has been shut down
Errno::ENOBUFS - insufficient resources are available in the system to complete the call
On Windows systems the following system exceptions may be raised if the call to listen fails:
Errno::ENETDOWN - the network is down
Errno::EADDRINUSE - the socket’s local address is already in use. This usually occurs during the execution of bind but could be delayed if the call to bind was to a partially wildcard address (involving ADDR_ANY) and if a specific address needs to be committed at the time of the call to listen
Errno::EINPROGRESS - a Windows Sockets 1.1 call is in progress or the service provider is still processing a callback function
Errno::EINVAL - the socket
has not been bound with a call to
bind.
Errno::EISCONN - the socket
is already connected
Errno::EMFILE - no more socket descriptors are available
Errno::ENOBUFS - no buffer space is available
Errno::ENOTSOC - socket
is not a socket
Errno::EOPNOTSUPP - the referenced socket
is not a type that
supports the listen method
listen manual pages on unix-based systems
listen function in Microsoft’s Winsock functions reference
VALUE rsock_sock_listen(VALUE sock, VALUE log) { rb_io_t *fptr; int backlog; backlog = NUM2INT(log); GetOpenFile(sock, fptr); if (listen(fptr->fd, backlog) < 0) rb_sys_fail("listen(2)"); return INT2FIX(0); }
Receives up to maxlen bytes from socket
.
flags is zero or more of the MSG_
options. The first
element of the results, mesg, is the data received. The second
element, sender_addrinfo, contains protocol-specific address
information of the sender.
maxlen
- the maximum number of bytes to receive from the
socket
flags
- zero or more of the MSG_
options
# In one file, start this first require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' ) socket.bind( sockaddr ) socket.listen( 5 ) client, client_addrinfo = socket.accept data = client.recvfrom( 20 )[0].chomp puts "I only received 20 bytes '#{data}'" sleep 1 socket.close # In another file, start this second require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' ) socket.connect( sockaddr ) socket.puts "Watch this get cut short!" socket.close
On unix-based based systems the following system exceptions may be raised if the call to recvfrom fails:
Errno::EAGAIN - the socket
file descriptor is marked as
O_NONBLOCK and no data is waiting to be received; or MSG_OOB is set and no out-of-band data is
available and either the socket
file descriptor is marked as
O_NONBLOCK or the socket
does not support blocking to wait for
out-of-band-data
Errno::EWOULDBLOCK - see Errno::EAGAIN
Errno::EBADF - the socket
is not a valid file descriptor
Errno::ECONNRESET - a connection was forcibly closed by a peer
Errno::EFAULT - the socket’s internal buffer, address or address length cannot be accessed or written
Errno::EINTR - a signal interrupted recvfrom before any data was available
Errno::EINVAL - the MSG_OOB flag is set and no out-of-band data is available
Errno::EIO - an i/o error occurred while reading from or writing to the filesystem
Errno::ENOBUFS - insufficient resources were available in the system to perform the operation
Errno::ENOMEM - insufficient memory was available to fulfill the request
Errno::ENOSR - there were insufficient STREAMS resources available to complete the operation
Errno::ENOTCONN - a receive is attempted on a connection-mode socket that is not connected
Errno::ENOTSOCK - the socket
does not refer to a socket
Errno::EOPNOTSUPP - the specified flags are not supported for this socket type
Errno::ETIMEDOUT - the connection timed out during connection establishment or due to a transmission timeout on an active connection
On Windows systems the following system exceptions may be raised if the call to recvfrom fails:
Errno::ENETDOWN - the network is down
Errno::EFAULT - the internal buffer and from parameters on
socket
are not part of the user address space, or the internal
fromlen parameter is too small to accommodate the peer address
Errno::EINTR - the (blocking) call was cancelled by an internal call to the WinSock function WSACancelBlockingCall
Errno::EINPROGRESS - a blocking Windows Sockets 1.1 call is in progress or the service provider is still processing a callback function
Errno::EINVAL - socket
has not been bound with a call to
bind, or an unknown flag was specified, or MSG_OOB was specified for a socket with SO_OOBINLINE enabled, or (for byte
stream-style sockets only) the internal len parameter on
socket
was zero or negative
Errno::EISCONN - socket
is already connected. The call to
recvfrom is not permitted with a connected socket on a socket that
is connection oriented or connectionless.
Errno::ENETRESET - the connection has been broken due to the keep-alive activity detecting a failure while the operation was in progress.
Errno::EOPNOTSUPP - MSG_OOB was
specified, but socket
is not stream-style such as type SOCK_STREAM. OOB data is not supported
in the communication domain associated with socket
, or
socket
is unidirectional and supports only send operations
Errno::ESHUTDOWN - socket
has been shutdown. It is not
possible to call recvfrom on a socket after shutdown has
been invoked.
Errno::EWOULDBLOCK - socket
is marked as nonblocking and a
call to recvfrom would block.
Errno::EMSGSIZE - the message was too large to fit into the specified buffer and was truncated.
Errno::ETIMEDOUT - the connection has been dropped, because of a network failure or because the system on the other end went down without notice
Errno::ECONNRESET - the virtual circuit was reset by the remote side executing a hard or abortive close. The application should close the socket; it is no longer usable. On a UDP-datagram socket this error indicates a previous send operation resulted in an ICMP Port Unreachable message.
static VALUE sock_recvfrom(int argc, VALUE *argv, VALUE sock) { return rsock_s_recvfrom(sock, argc, argv, RECV_SOCKET); }
Receives up to maxlen bytes from socket
using
recvfrom(2) after O_NONBLOCK is set for the underlying file descriptor.
flags is zero or more of the MSG_
options. The first
element of the results, mesg, is the data received. The second
element, sender_addrinfo, contains protocol-specific address
information of the sender.
When recvfrom(2) returns 0, #recvfrom_nonblock returns an empty string as data. The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
maxlen
- the maximum number of bytes to receive from the
socket
flags
- zero or more of the MSG_
options
outbuf
- destination String buffer
opts
- keyword hash, supporting `exception: false`
# In one file, start this first require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.bind(sockaddr) socket.listen(5) client, client_addrinfo = socket.accept begin # emulate blocking recvfrom pair = client.recvfrom_nonblock(20) rescue IO::WaitReadable IO.select([client]) retry end data = pair[0].chomp puts "I only received 20 bytes '#{data}'" sleep 1 socket.close # In another file, start this second require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.connect(sockaddr) socket.puts "Watch this get cut short!" socket.close
Refer to #recvfrom for the exceptions that may be thrown if the call to recvfrom_nonblock fails.
#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying recvfrom_nonblock.
By specifying a keyword argument exception to false
,
you can indicate that #recvfrom_nonblock should
not raise an IO::WaitReadable exception, but return the symbol
:wait_readable
instead.
# File socket/lib/socket.rb, line 535 def recvfrom_nonblock(len, flag = 0, str = nil, exception: true) __recvfrom_nonblock(len, flag, str, exception) end
Accepts an incoming connection returning an array containing the (integer) file descriptor for the incoming connection, client_socket_fd, and an Addrinfo, client_addrinfo.
# In one script, start this first require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' ) socket.bind( sockaddr ) socket.listen( 5 ) client_fd, client_addrinfo = socket.sysaccept client_socket = Socket.for_fd( client_fd ) puts "The client said, '#{client_socket.readline.chomp}'" client_socket.puts "Hello from script one!" socket.close # In another script, start this second require 'socket' include Socket::Constants socket = Socket.new( AF_INET, SOCK_STREAM, 0 ) sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' ) socket.connect( sockaddr ) socket.puts "Hello from script 2." puts "The server said, '#{socket.readline.chomp}'" socket.close
Refer to #accept for the exceptions that may be thrown if the call to sysaccept fails.
static VALUE sock_sysaccept(VALUE sock) { rb_io_t *fptr; VALUE sock2; union_sockaddr buf; socklen_t len = (socklen_t)sizeof buf; GetOpenFile(sock, fptr); sock2 = rsock_s_accept(0,fptr->fd,&buf.addr,&len); return rb_assoc_new(sock2, rsock_io_socket_addrinfo(sock2, &buf.addr, len)); }