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module Socket::Constants
Socket::Constants provides socket-related constants. All possible socket constants are listed in the documentation but they may not all be present on your platform.
If the underlying platform doesn't define a constant the corresponding Ruby constant is not defined.
Constants
- AF_APPLETALK
- 
      AppleTalk protocol 
- AF_ATM
- 
      Asynchronous Transfer Mode 
- AF_AX25
- 
      AX.25 protocol 
- AF_CCITT
- 
      CCITT (now ITU-T) protocols 
- AF_CHAOS
- 
      MIT CHAOS protocols 
- AF_CNT
- 
      Computer Network Technology 
- AF_COIP
- 
      Connection-oriented IP 
- AF_DATAKIT
- 
      Datakit protocol 
- AF_DEC
- 
      DECnet protocol 
- AF_DLI
- 
      DEC Direct Data Link Interface protocol 
- AF_E164
- 
      CCITT (ITU-T) E.164 recommendation 
- AF_ECMA
- 
      European Computer Manufacturers protocols 
- AF_HYLINK
- 
      NSC Hyperchannel protocol 
- AF_IMPLINK
- 
      ARPANET IMP protocol 
- AF_INET
- 
      IPv4 protocol 
- AF_INET6
- 
      IPv6 protocol 
- AF_IPX
- 
      IPX protocol 
- AF_ISDN
- 
      Integrated Services Digital Network 
- AF_ISO
- 
      ISO Open Systems Interconnection protocols 
- AF_LAT
- 
      Local Area Transport protocol 
- AF_LINK
- 
      Link layer interface 
- AF_LOCAL
- 
      Host-internal protocols 
- AF_MAX
- 
      Maximum address family for this platform 
- AF_NATM
- 
      Native ATM access 
- AF_NDRV
- 
      Network driver raw access 
- AF_NETBIOS
- 
      NetBIOS 
- AF_NETGRAPH
- 
      Netgraph sockets 
- AF_NS
- 
      XEROX NS protocols 
- AF_OSI
- 
      ISO Open Systems Interconnection protocols 
- AF_PACKET
- 
      Direct link-layer access 
- AF_PPP
- 
      Point-to-Point Protocol 
- AF_PUP
- 
      PARC Universal Packet protocol 
- AF_ROUTE
- 
      Internal routing protocol 
- AF_SIP
- 
      Simple Internet Protocol 
- AF_SNA
- 
      IBM SNA protocol 
- AF_SYSTEM
- AF_UNIX
- 
      UNIX sockets 
- AF_UNSPEC
- 
      Unspecified protocol, any supported address family 
- AI_ADDRCONFIG
- 
      Accept only if any address is assigned 
- AI_ALL
- 
      Allow all addresses 
- AI_CANONNAME
- 
      Fill in the canonical name 
- AI_DEFAULT
- 
      Default flags for getaddrinfo 
- AI_MASK
- 
      Valid flag mask for getaddrinfo (not for application use) 
- AI_NUMERICHOST
- 
      Prevent host name resolution 
- AI_NUMERICSERV
- 
      Prevent service name resolution 
- AI_PASSIVE
- 
      Get address to use with bind() 
- AI_V4MAPPED
- 
      Accept IPv4-mapped IPv6 addresses 
- AI_V4MAPPED_CFG
- 
      Accept IPv4 mapped addresses if the kernel supports it 
- EAI_ADDRFAMILY
- 
      Address family for hostname not supported 
- EAI_AGAIN
- 
      Temporary failure in name resolution 
- EAI_BADFLAGS
- 
      Invalid flags 
- EAI_BADHINTS
- 
      Invalid value for hints 
- EAI_FAIL
- 
      Non-recoverable failure in name resolution 
- EAI_FAMILY
- 
      Address family not supported 
- EAI_MAX
- 
      Maximum error code from getaddrinfo 
- EAI_MEMORY
- 
      Memory allocation failure 
- EAI_NODATA
- 
      No address associated with hostname 
- EAI_NONAME
- 
      Hostname nor servname, or not known 
- EAI_OVERFLOW
- 
      Argument buffer overflow 
- EAI_PROTOCOL
- 
      Resolved protocol is unknown 
- EAI_SERVICE
- 
      Servname not supported for socket type 
- EAI_SOCKTYPE
- 
      Socket type not supported 
- EAI_SYSTEM
- 
      System error returned in errno 
- IFF_802_1Q_VLAN
- 
      802.1Q VLAN device 
- IFF_ALLMULTI
- 
      receive all multicast packets 
- IFF_ALTPHYS
- 
      use alternate physical connection 
- IFF_AUTOMEDIA
- 
      auto media select active 
- IFF_BONDING
- 
      bonding master or slave 
- IFF_BRIDGE_PORT
- 
      device used as bridge port 
- IFF_BROADCAST
- 
      broadcast address valid 
- IFF_CANTCHANGE
- 
      flags not changeable 
- IFF_CANTCONFIG
- 
      unconfigurable using ioctl(2) 
- IFF_DEBUG
- 
      turn on debugging 
- IFF_DISABLE_NETPOLL
- 
      disable netpoll at run-time 
- IFF_DONT_BRIDGE
- 
      disallow bridging this ether dev 
- IFF_DORMANT
- 
      driver signals dormant 
- IFF_DRV_OACTIVE
- 
      tx hardware queue is full 
- IFF_DRV_RUNNING
- 
      resources allocated 
- IFF_DYING
- 
      interface is winding down 
- IFF_DYNAMIC
- 
      dialup device with changing addresses 
- IFF_EBRIDGE
- 
      ethernet bridging device 
- IFF_ECHO
- 
      echo sent packets 
- IFF_ISATAP
- 
      ISATAP interface (RFC4214) 
- IFF_LINK0
- 
      per link layer defined bit 0 
- IFF_LINK1
- 
      per link layer defined bit 1 
- IFF_LINK2
- 
      per link layer defined bit 2 
- IFF_LIVE_ADDR_CHANGE
- 
      hardware address change when it's running 
- IFF_LOOPBACK
- 
      loopback net 
- IFF_LOWER_UP
- 
      driver signals L1 up 
- IFF_MACVLAN_PORT
- 
      device used as macvlan port 
- IFF_MASTER
- 
      master of a load balancer 
- IFF_MASTER_8023AD
- 
      bonding master, 802.3ad. 
- IFF_MASTER_ALB
- 
      bonding master, balance-alb. 
- IFF_MASTER_ARPMON
- 
      bonding master, ARP mon in use 
- IFF_MONITOR
- 
      user-requested monitor mode 
- IFF_MULTICAST
- 
      supports multicast 
- IFF_NOARP
- 
      no address resolution protocol 
- IFF_NOTRAILERS
- 
      avoid use of trailers 
- IFF_OACTIVE
- 
      transmission in progress 
- IFF_OVS_DATAPATH
- 
      device used as Open vSwitch datapath port 
- IFF_POINTOPOINT
- 
      point-to-point link 
- IFF_PORTSEL
- 
      can set media type 
- IFF_PPROMISC
- 
      user-requested promisc mode 
- IFF_PROMISC
- 
      receive all packets 
- IFF_RENAMING
- 
      interface is being renamed 
- IFF_ROUTE
- 
      routing entry installed 
- IFF_RUNNING
- 
      resources allocated 
- IFF_SIMPLEX
- 
      can't hear own transmissions 
- IFF_SLAVE
- 
      slave of a load balancer 
- IFF_SLAVE_INACTIVE
- 
      bonding slave not the curr. active 
- IFF_SLAVE_NEEDARP
- 
      need ARPs for validation 
- IFF_SMART
- 
      interface manages own routes 
- IFF_STATICARP
- 
      static ARP 
- IFF_SUPP_NOFCS
- 
      sending custom FCS 
- IFF_TEAM_PORT
- 
      used as team port 
- IFF_TX_SKB_SHARING
- 
      sharing skbs on transmit 
- IFF_UNICAST_FLT
- 
      unicast filtering 
- IFF_UP
- 
      interface is up 
- IFF_VOLATILE
- 
      volatile flags 
- IFF_WAN_HDLC
- 
      WAN HDLC device 
- IFF_XMIT_DST_RELEASE
- 
      dev_hard_start_xmit() is allowed to release skb->dst 
- IFNAMSIZ
- 
      Maximum interface name size 
- IF_NAMESIZE
- 
      Maximum interface name size 
- INADDR_ALLHOSTS_GROUP
- 
      Multicast group for all systems on this subset 
- INADDR_ANY
- 
      A socket bound to INADDR_ANY receives packets from all interfaces and sends from the default IP address 
- INADDR_BROADCAST
- 
      The network broadcast address 
- INADDR_LOOPBACK
- 
      The loopback address 
- INADDR_MAX_LOCAL_GROUP
- 
      The last local network multicast group 
- INADDR_NONE
- 
      A bitmask for matching no valid IP address 
- INADDR_UNSPEC_GROUP
- 
      The reserved multicast group 
- INET6_ADDRSTRLEN
- 
      Maximum length of an IPv6 address string 
- INET_ADDRSTRLEN
- 
      Maximum length of an IPv4 address string 
- IPPORT_RESERVED
- 
      Default minimum address for bind or connect 
- IPPORT_USERRESERVED
- 
      Default maximum address for bind or connect 
- IPPROTO_AH
- 
      IP6 auth header 
- IPPROTO_BIP
- IPPROTO_DSTOPTS
- 
      IP6 destination option 
- IPPROTO_EGP
- 
      Exterior Gateway Protocol 
- IPPROTO_EON
- 
      ISO cnlp 
- IPPROTO_ESP
- 
      IP6 Encapsulated Security Payload 
- IPPROTO_FRAGMENT
- 
      IP6 fragmentation header 
- IPPROTO_GGP
- 
      Gateway to Gateway Protocol 
- IPPROTO_HELLO
- 
      “hello” routing protocol 
- IPPROTO_HOPOPTS
- 
      IP6 hop-by-hop options 
- IPPROTO_ICMP
- 
      Control message protocol 
- IPPROTO_ICMPV6
- 
      ICMP6 
- IPPROTO_IDP
- 
      XNS IDP 
- IPPROTO_IGMP
- 
      Group Management Protocol 
- IPPROTO_IP
- 
      Dummy protocol for IP 
- IPPROTO_IPV6
- 
      IP6 header 
- IPPROTO_MAX
- 
      Maximum IPPROTO constant 
- IPPROTO_ND
- 
      Sun net disk protocol 
- IPPROTO_NONE
- 
      IP6 no next header 
- IPPROTO_PUP
- 
      PARC Universal Packet protocol 
- IPPROTO_RAW
- 
      Raw IP packet 
- IPPROTO_ROUTING
- 
      IP6 routing header 
- IPPROTO_TCP
- 
      TCP 
- IPPROTO_TP
- 
      ISO transport protocol class 4 
- IPPROTO_UDP
- 
      UDP 
- IPPROTO_XTP
- 
      Xpress Transport Protocol 
- IPV6_CHECKSUM
- 
      Checksum offset for raw sockets 
- IPV6_DONTFRAG
- 
      Don't fragment packets 
- IPV6_DSTOPTS
- 
      Destination option 
- IPV6_HOPLIMIT
- 
      Hop limit 
- IPV6_HOPOPTS
- 
      Hop-by-hop option 
- IPV6_JOIN_GROUP
- 
      Join a group membership 
- IPV6_LEAVE_GROUP
- 
      Leave a group membership 
- IPV6_MULTICAST_HOPS
- 
      IP6 multicast hops 
- IPV6_MULTICAST_IF
- 
      IP6 multicast interface 
- IPV6_MULTICAST_LOOP
- 
      IP6 multicast loopback 
- IPV6_NEXTHOP
- 
      Next hop address 
- IPV6_PATHMTU
- 
      Retrieve current path MTU 
- IPV6_PKTINFO
- 
      Receive packet information with datagram 
- IPV6_RECVDSTOPTS
- 
      Receive all IP6 options for response 
- IPV6_RECVHOPLIMIT
- 
      Receive hop limit with datagram 
- IPV6_RECVHOPOPTS
- 
      Receive hop-by-hop options 
- IPV6_RECVPATHMTU
- 
      Receive current path MTU with datagram 
- IPV6_RECVPKTINFO
- 
      Receive destination IP address and incoming interface 
- IPV6_RECVRTHDR
- 
      Receive routing header 
- IPV6_RECVTCLASS
- 
      Receive traffic class 
- IPV6_RTHDR
- 
      Allows removal of sticky routing headers 
- IPV6_RTHDRDSTOPTS
- 
      Allows removal of sticky destination options header 
- IPV6_RTHDR_TYPE_0
- 
      Routing header type 0 
- IPV6_TCLASS
- 
      Specify the traffic class 
- IPV6_UNICAST_HOPS
- 
      IP6 unicast hops 
- IPV6_USE_MIN_MTU
- 
      Use the minimum MTU size 
- IPV6_V6ONLY
- 
      Only bind IPv6 with a wildcard bind 
- IPX_TYPE
- IP_ADD_MEMBERSHIP
- 
      Add a multicast group membership 
- IP_ADD_SOURCE_MEMBERSHIP
- 
      Add a multicast group membership 
- IP_BLOCK_SOURCE
- 
      Block IPv4 multicast packets with a give source address 
- IP_DEFAULT_MULTICAST_LOOP
- 
      Default multicast loopback 
- IP_DEFAULT_MULTICAST_TTL
- 
      Default multicast TTL 
- IP_DONTFRAG
- 
      Don't fragment packets 
- IP_DROP_MEMBERSHIP
- 
      Drop a multicast group membership 
- IP_DROP_SOURCE_MEMBERSHIP
- 
      Drop a multicast group membership 
- IP_FREEBIND
- 
      Allow binding to nonexistent IP addresses 
- IP_HDRINCL
- 
      Header is included with data 
- IP_IPSEC_POLICY
- 
      IPsec security policy 
- IP_MAX_MEMBERSHIPS
- 
      Maximum number multicast groups a socket can join 
- IP_MINTTL
- 
      Minimum TTL allowed for received packets 
- IP_MSFILTER
- 
      Multicast source filtering 
- IP_MTU
- 
      The Maximum Transmission Unit of the socket 
- IP_MTU_DISCOVER
- 
      Path MTU discovery 
- IP_MULTICAST_IF
- 
      IP multicast interface 
- IP_MULTICAST_LOOP
- 
      IP multicast loopback 
- IP_MULTICAST_TTL
- 
      IP multicast TTL 
- IP_ONESBCAST
- 
      Force outgoing broadcast datagrams to have the undirected broadcast address 
- IP_OPTIONS
- 
      IP options to be included in packets 
- IP_PASSSEC
- 
      Retrieve security context with datagram 
- IP_PKTINFO
- 
      Receive packet information with datagrams 
- IP_PKTOPTIONS
- 
      Receive packet options with datagrams 
- IP_PMTUDISC_DO
- 
      Always send DF frames 
- IP_PMTUDISC_DONT
- 
      Never send DF frames 
- IP_PMTUDISC_WANT
- 
      Use per-route hints 
- IP_PORTRANGE
- 
      Set the port range for sockets with unspecified port numbers 
- IP_RECVDSTADDR
- 
      Receive IP destination address with datagram 
- IP_RECVERR
- 
      Enable extended reliable error message passing 
- IP_RECVIF
- 
      Receive interface information with datagrams 
- IP_RECVOPTS
- 
      Receive all IP options with datagram 
- IP_RECVRETOPTS
- 
      Receive all IP options for response 
- IP_RECVSLLA
- 
      Receive link-layer address with datagrams 
- IP_RECVTOS
- 
      Receive TOS with incoming packets 
- IP_RECVTTL
- 
      Receive IP TTL with datagrams 
- IP_RETOPTS
- 
      IP options to be included in datagrams 
- IP_ROUTER_ALERT
- 
      Notify transit routers to more closely examine the contents of an IP packet 
- IP_SENDSRCADDR
- 
      Source address for outgoing UDP datagrams 
- IP_TOS
- 
      IP type-of-service 
- IP_TRANSPARENT
- 
      Transparent proxy 
- IP_TTL
- 
      IP time-to-live 
- IP_UNBLOCK_SOURCE
- 
      Unblock IPv4 multicast packets with a give source address 
- IP_XFRM_POLICY
- LOCAL_CONNWAIT
- 
      Connect blocks until accepted 
- LOCAL_CREDS
- 
      Pass credentials to receiver 
- LOCAL_PEERCRED
- 
      Retrieve peer credentials 
- MCAST_BLOCK_SOURCE
- 
      Block multicast packets from this source 
- MCAST_EXCLUDE
- 
      Exclusive multicast source filter 
- MCAST_INCLUDE
- 
      Inclusive multicast source filter 
- MCAST_JOIN_GROUP
- 
      Join a multicast group 
- MCAST_JOIN_SOURCE_GROUP
- 
      Join a multicast source group 
- MCAST_LEAVE_GROUP
- 
      Leave a multicast group 
- MCAST_LEAVE_SOURCE_GROUP
- 
      Leave a multicast source group 
- MCAST_MSFILTER
- 
      Multicast source filtering 
- MCAST_UNBLOCK_SOURCE
- 
      Unblock multicast packets from this source 
- MSG_COMPAT
- 
      End of record 
- MSG_CONFIRM
- 
      Confirm path validity 
- MSG_CTRUNC
- 
      Control data lost before delivery 
- MSG_DONTROUTE
- 
      Send without using the routing tables 
- MSG_DONTWAIT
- 
      This message should be non-blocking 
- MSG_EOF
- 
      Data completes connection 
- MSG_EOR
- 
      Data completes record 
- MSG_ERRQUEUE
- 
      Fetch message from error queue 
- MSG_FASTOPEN
- 
      Reduce step of the handshake process 
- MSG_FIN
- MSG_FLUSH
- 
      Start of a hold sequence. Dumps to so_temp 
- MSG_HAVEMORE
- 
      Data ready to be read 
- MSG_HOLD
- 
      Hold fragment in so_temp 
- MSG_MORE
- 
      Sender will send more 
- MSG_NOSIGNAL
- 
      Do not generate SIGPIPE 
- MSG_OOB
- 
      Process out-of-band data 
- MSG_PEEK
- 
      Peek at incoming message 
- MSG_PROXY
- 
      Wait for full request 
- MSG_RCVMORE
- 
      Data remains in the current packet 
- MSG_RST
- MSG_SEND
- 
      Send the packet in so_temp 
- MSG_SYN
- MSG_TRUNC
- 
      Data discarded before delivery 
- MSG_WAITALL
- 
      Wait for full request or error 
- NI_DGRAM
- 
      The service specified is a datagram service (looks up UDP ports) 
- NI_MAXHOST
- 
      Maximum length of a hostname 
- NI_MAXSERV
- 
      Maximum length of a service name 
- NI_NAMEREQD
- 
      A name is required 
- NI_NOFQDN
- 
      An FQDN is not required for local hosts, return only the local part 
- NI_NUMERICHOST
- 
      Return a numeric address 
- NI_NUMERICSERV
- 
      Return the service name as a digit string 
- PF_APPLETALK
- 
      AppleTalk protocol 
- PF_ATM
- 
      Asynchronous Transfer Mode 
- PF_AX25
- 
      AX.25 protocol 
- PF_CCITT
- 
      CCITT (now ITU-T) protocols 
- PF_CHAOS
- 
      MIT CHAOS protocols 
- PF_CNT
- 
      Computer Network Technology 
- PF_COIP
- 
      Connection-oriented IP 
- PF_DATAKIT
- 
      Datakit protocol 
- PF_DEC
- 
      DECnet protocol 
- PF_DLI
- 
      DEC Direct Data Link Interface protocol 
- PF_ECMA
- 
      European Computer Manufacturers protocols 
- PF_HYLINK
- 
      NSC Hyperchannel protocol 
- PF_IMPLINK
- 
      ARPANET IMP protocol 
- PF_INET
- 
      IPv4 protocol 
- PF_INET6
- 
      IPv6 protocol 
- PF_IPX
- 
      IPX protocol 
- PF_ISDN
- 
      Integrated Services Digital Network 
- PF_ISO
- 
      ISO Open Systems Interconnection protocols 
- PF_KEY
- PF_LAT
- 
      Local Area Transport protocol 
- PF_LINK
- 
      Link layer interface 
- PF_LOCAL
- 
      Host-internal protocols 
- PF_MAX
- 
      Maximum address family for this platform 
- PF_NATM
- 
      Native ATM access 
- PF_NDRV
- 
      Network driver raw access 
- PF_NETBIOS
- 
      NetBIOS 
- PF_NETGRAPH
- 
      Netgraph sockets 
- PF_NS
- 
      XEROX NS protocols 
- PF_OSI
- 
      ISO Open Systems Interconnection protocols 
- PF_PACKET
- 
      Direct link-layer access 
- PF_PIP
- PF_PPP
- 
      Point-to-Point Protocol 
- PF_PUP
- 
      PARC Universal Packet protocol 
- PF_ROUTE
- 
      Internal routing protocol 
- PF_RTIP
- PF_SIP
- 
      Simple Internet Protocol 
- PF_SNA
- 
      IBM SNA protocol 
- PF_SYSTEM
- PF_UNIX
- 
      UNIX sockets 
- PF_UNSPEC
- 
      Unspecified protocol, any supported address family 
- PF_XTP
- 
      eXpress Transfer Protocol 
- SCM_BINTIME
- 
      Timestamp (bintime) 
- SCM_CREDENTIALS
- 
      The sender's credentials 
- SCM_CREDS
- 
      Process credentials 
- SCM_RIGHTS
- 
      Access rights 
- SCM_TIMESTAMP
- 
      Timestamp (timeval) 
- SCM_TIMESTAMPING
- 
      Timestamp (timespec list) (Linux 2.6.30) 
- SCM_TIMESTAMPNS
- 
      Timespec (timespec) 
- SCM_UCRED
- 
      User credentials 
- SCM_WIFI_STATUS
- 
      Wifi status (Linux 3.3) 
- SHUT_RD
- 
      Shut down the reading side of the socket 
- SHUT_RDWR
- 
      Shut down the both sides of the socket 
- SHUT_WR
- 
      Shut down the writing side of the socket 
- SOCK_DGRAM
- 
      A datagram socket provides connectionless, unreliable messaging 
- SOCK_PACKET
- 
      Device-level packet access 
- SOCK_RAW
- 
      A raw socket provides low-level access for direct access or implementing network protocols 
- SOCK_RDM
- 
      A reliable datagram socket provides reliable delivery of messages 
- SOCK_SEQPACKET
- 
      A sequential packet socket provides sequenced, reliable two-way connection for datagrams 
- SOCK_STREAM
- 
      A stream socket provides a sequenced, reliable two-way connection for a byte stream 
- SOL_ATALK
- 
      AppleTalk socket options 
- SOL_AX25
- 
      AX.25 socket options 
- SOL_IP
- 
      IP socket options 
- SOL_IPX
- 
      IPX socket options 
- SOL_SOCKET
- 
      Socket-level options 
- SOL_TCP
- 
      TCP socket options 
- SOL_UDP
- 
      UDP socket options 
- SOMAXCONN
- 
      Maximum connection requests that may be queued for a socket 
- SOPRI_BACKGROUND
- 
      Background socket priority 
- SOPRI_INTERACTIVE
- 
      Interactive socket priority 
- SOPRI_NORMAL
- 
      Normal socket priority 
- SO_ACCEPTCONN
- 
      Socket has had listen() called on it 
- SO_ACCEPTFILTER
- 
      There is an accept filter 
- SO_ALLZONES
- 
      Bypass zone boundaries 
- SO_ATTACH_FILTER
- 
      Attach an accept filter 
- SO_BINDTODEVICE
- 
      Only send packets from the given interface 
- SO_BINTIME
- 
      Receive timestamp with datagrams (bintime) 
- SO_BPF_EXTENSIONS
- 
      Query supported BPF extensions (Linux 3.14) 
- SO_BROADCAST
- 
      Permit sending of broadcast messages 
- SO_BUSY_POLL
- 
      Set the threshold in microseconds for low latency polling (Linux 3.11) 
- SO_DEBUG
- 
      Debug info recording 
- SO_DETACH_FILTER
- 
      Detach an accept filter 
- SO_DOMAIN
- 
      Domain given for socket() (Linux 2.6.32) 
- SO_DONTROUTE
- 
      Use interface addresses 
- SO_DONTTRUNC
- 
      Retain unread data 
- SO_ERROR
- 
      Get and clear the error status 
- SO_GET_FILTER
- 
      Obtain filter set by SO_ATTACH_FILTER (Linux 3.8) 
- SO_KEEPALIVE
- 
      Keep connections alive 
- SO_LINGER
- 
      Linger on close if data is present 
- SO_LOCK_FILTER
- 
      Lock the filter attached to a socket (Linux 3.9) 
- SO_MAC_EXEMPT
- 
      Mandatory Access Control exemption for unlabeled peers 
- SO_MARK
- 
      Set the mark for mark-based routing (Linux 2.6.25) 
- SO_MAX_PACING_RATE
- 
      Cap the rate computed by transport layer. [bytes per second] (Linux 3.13) 
- SO_NKE
- 
      Install socket-level Network Kernel Extension 
- SO_NOFCS
- 
      Set netns of a socket (Linux 3.4) 
- SO_NOSIGPIPE
- 
      Don't SIGPIPE on EPIPE 
- SO_NO_CHECK
- 
      Disable checksums 
- SO_NREAD
- 
      Get first packet byte count 
- SO_OOBINLINE
- 
      Leave received out-of-band data in-line 
- SO_PASSCRED
- 
      Receive SCM_CREDENTIALS messages 
- SO_PASSSEC
- 
      Toggle security context passing (Linux 2.6.18) 
- SO_PEEK_OFF
- 
      Set the peek offset (Linux 3.4) 
- SO_PEERCRED
- 
      The credentials of the foreign process connected to this socket 
- SO_PEERNAME
- 
      Name of the connecting user 
- SO_PEERSEC
- 
      Obtain the security credentials (Linux 2.6.2) 
- SO_PRIORITY
- 
      The protocol-defined priority for all packets on this socket 
- SO_PROTOCOL
- 
      Protocol given for socket() (Linux 2.6.32) 
- SO_RCVBUF
- 
      Receive buffer size 
- SO_RCVBUFFORCE
- 
      Receive buffer size without rmem_max limit (Linux 2.6.14) 
- SO_RCVLOWAT
- 
      Receive low-water mark 
- SO_RCVTIMEO
- 
      Receive timeout 
- SO_RECVUCRED
- 
      Receive user credentials with datagram 
- SO_REUSEADDR
- 
      Allow local address reuse 
- SO_REUSEPORT
- 
      Allow local address and port reuse 
- SO_RXQ_OVFL
- 
      Toggle cmsg for number of packets dropped (Linux 2.6.33) 
- SO_SECURITY_AUTHENTICATION
- SO_SECURITY_ENCRYPTION_NETWORK
- SO_SECURITY_ENCRYPTION_TRANSPORT
- SO_SELECT_ERR_QUEUE
- 
      Make select() detect socket error queue with errorfds (Linux 3.10) 
- SO_SNDBUF
- 
      Send buffer size 
- SO_SNDBUFFORCE
- 
      Send buffer size without wmem_max limit (Linux 2.6.14) 
- SO_SNDLOWAT
- 
      Send low-water mark 
- SO_SNDTIMEO
- 
      Send timeout 
- SO_TIMESTAMP
- 
      Receive timestamp with datagrams (timeval) 
- SO_TIMESTAMPING
- 
      Time stamping of incoming and outgoing packets (Linux 2.6.30) 
- SO_TIMESTAMPNS
- 
      Receive nanosecond timestamp with datagrams (timespec) 
- SO_TYPE
- 
      Get the socket type 
- SO_USELOOPBACK
- 
      Bypass hardware when possible 
- SO_WANTMORE
- 
      Give a hint when more data is ready 
- SO_WANTOOBFLAG
- 
      OOB data is wanted in MSG_FLAG on receive 
- SO_WIFI_STATUS
- 
      Toggle cmsg for wifi status (Linux 3.3) 
- TCP_CONGESTION
- 
      TCP congestion control algorithm (Linux 2.6.13, glibc 2.6) 
- TCP_COOKIE_TRANSACTIONS
- 
      TCP Cookie Transactions (Linux 2.6.33, glibc 2.18) 
- TCP_CORK
- 
      Don't send partial frames (Linux 2.2, glibc 2.2) 
- TCP_DEFER_ACCEPT
- 
      Don't notify a listening socket until data is ready (Linux 2.4, glibc 2.2) 
- TCP_FASTOPEN
- 
      Reduce step of the handshake process (Linux 3.7, glibc 2.18) 
- TCP_INFO
- 
      Retrieve information about this socket (Linux 2.4, glibc 2.2) 
- TCP_KEEPCNT
- 
      Maximum number of keepalive probes allowed before dropping a connection (Linux 2.4, glibc 2.2) 
- TCP_KEEPIDLE
- 
      Idle time before keepalive probes are sent (Linux 2.4, glibc 2.2) 
- TCP_KEEPINTVL
- 
      Time between keepalive probes (Linux 2.4, glibc 2.2) 
- TCP_LINGER2
- 
      Lifetime of orphaned FIN_WAIT2 sockets (Linux 2.4, glibc 2.2) 
- TCP_MAXSEG
- 
      Set maximum segment size 
- TCP_MD5SIG
- 
      Use MD5 digests (RFC2385, Linux 2.6.20, glibc 2.7) 
- TCP_NODELAY
- 
      Don't delay sending to coalesce packets 
- TCP_NOOPT
- 
      Don't use TCP options 
- TCP_NOPUSH
- 
      Don't push the last block of write 
- TCP_QUEUE_SEQ
- 
      Sequence of a queue for repair mode (Linux 3.5, glibc 2.18) 
- TCP_QUICKACK
- 
      Enable quickack mode (Linux 2.4.4, glibc 2.3) 
- TCP_REPAIR
- 
      Repair mode (Linux 3.5, glibc 2.18) 
- TCP_REPAIR_OPTIONS
- 
      Options for repair mode (Linux 3.5, glibc 2.18) 
- TCP_REPAIR_QUEUE
- 
      Queue for repair mode (Linux 3.5, glibc 2.18) 
- TCP_SYNCNT
- 
      Number of SYN retransmits before a connection is dropped (Linux 2.4, glibc 2.2) 
- TCP_THIN_DUPACK
- 
      Duplicated acknowledgments handling for thin-streams (Linux 2.6.34, glibc 2.18) 
- TCP_THIN_LINEAR_TIMEOUTS
- 
      Linear timeouts for thin-streams (Linux 2.6.34, glibc 2.18) 
- TCP_TIMESTAMP
- 
      TCP timestamp (Linux 3.9, glibc 2.18) 
- TCP_USER_TIMEOUT
- 
      Max timeout before a TCP connection is aborted (Linux 2.6.37, glibc 2.18) 
- TCP_WINDOW_CLAMP
- 
      Clamp the size of the advertised window (Linux 2.4, glibc 2.2) 
- UDP_CORK
- 
      Don't send partial frames (Linux 2.5.44, glibc 2.11) 
Ruby Core © 1993–2017 Yukihiro Matsumoto
Licensed under the Ruby License.
Ruby Standard Library © contributors
Licensed under their own licenses.