diff --git a/stdlib/2and3/socket.pyi b/stdlib/2and3/socket.pyi
index 93052b814..79e03cf21 100644
--- a/stdlib/2and3/socket.pyi
+++ b/stdlib/2and3/socket.pyi
@@ -10,246 +10,399 @@ from typing import Any, Tuple, List, Optional, Union, overload
 
 # ----- variables and constants -----
 
-AF_UNIX = 0
-AF_INET = 0
-AF_INET6 = 0
-SOCK_STREAM = 0
-SOCK_DGRAM = 0
-SOCK_RAW = 0
-SOCK_RDM = 0
-SOCK_SEQPACKET = 0
-SOCK_CLOEXEC = 0
-SOCK_NONBLOCK = 0
-SOMAXCONN = 0
-has_ipv6 = False
-_GLOBAL_DEFAULT_TIMEOUT = ...  # type: Any
-SocketType = ...  # type: Any
-SocketIO = ...  # type: Any
+AF_UNIX: int
+AF_INET: int
+AF_INET6: int
+SOCK_STREAM: int
+SOCK_DGRAM: int
+SOCK_RAW: int
+SOCK_RDM: int
+SOCK_SEQPACKET: int
+SOCK_CLOEXEC: int
+SOCK_NONBLOCK: int
+SOMAXCONN: int
+has_ipv6: bool
+_GLOBAL_DEFAULT_TIMEOUT: Any
+SocketType: Any
+SocketIO: Any
 
+# These are flags that may exist on Python 3.6. Many don't exist on all platforms.
+AF_AAL5: int
+AF_APPLETALK: int
+AF_ASH: int
+AF_ATMPVC: int
+AF_ATMSVC: int
+AF_AX25: int
+AF_BLUETOOTH: int
+AF_BRIDGE: int
+AF_CAN: int
+AF_DECnet: int
+AF_ECONET: int
+AF_IPX: int
+AF_IRDA: int
+AF_KEY: int
+AF_LLC: int
+AF_NETBEUI: int
+AF_NETLINK: int
+AF_NETROM: int
+AF_PACKET: int
+AF_PPPOX: int
+AF_RDS: int
+AF_ROSE: int
+AF_ROUTE: int
+AF_SECURITY: int
+AF_SNA: int
+AF_SYSTEM: int
+AF_TIPC: int
+AF_UNSPEC: int
+AF_WANPIPE: int
+AF_X25: int
+AI_ADDRCONFIG: int
+AI_ALL: int
+AI_CANONNAME: int
+AI_DEFAULT: int
+AI_MASK: int
+AI_NUMERICHOST: int
+AI_NUMERICSERV: int
+AI_PASSIVE: int
+AI_V4MAPPED: int
+AI_V4MAPPED_CFG: int
+BDADDR_ANY: str
+BDADDR_LOCAL: str
+BTPROTO_HCI: int
+BTPROTO_L2CAP: int
+BTPROTO_RFCOMM: int
+BTPROTO_SCO: int
+CAN_EFF_FLAG: int
+CAN_EFF_MASK: int
+CAN_ERR_FLAG: int
+CAN_ERR_MASK: int
+CAN_RAW: int
+CAN_RAW_ERR_FILTER: int
+CAN_RAW_FILTER: int
+CAN_RAW_LOOPBACK: int
+CAN_RAW_RECV_OWN_MSGS: int
+CAN_RTR_FLAG: int
+CAN_SFF_MASK: int
+CAPI: int
+EAGAIN: int
+EAI_ADDRFAMILY: int
+EAI_AGAIN: int
+EAI_BADFLAGS: int
+EAI_BADHINTS: int
+EAI_FAIL: int
+EAI_FAMILY: int
+EAI_MAX: int
+EAI_MEMORY: int
+EAI_NODATA: int
+EAI_NONAME: int
+EAI_OVERFLOW: int
+EAI_PROTOCOL: int
+EAI_SERVICE: int
+EAI_SOCKTYPE: int
+EAI_SYSTEM: int
+EBADF: int
+EINTR: int
+EWOULDBLOCK: int
+HCI_DATA_DIR: int
+HCI_FILTER: int
+HCI_TIME_STAMP: int
+INADDR_ALLHOSTS_GROUP: int
+INADDR_ANY: int
+INADDR_BROADCAST: int
+INADDR_LOOPBACK: int
+INADDR_MAX_LOCAL_GROUP: int
+INADDR_NONE: int
+INADDR_UNSPEC_GROUP: int
+IPPORT_RESERVED: int
+IPPORT_USERRESERVED: int
+IPPROTO_AH: int
+IPPROTO_BIP: int
+IPPROTO_DSTOPTS: int
+IPPROTO_EGP: int
+IPPROTO_EON: int
+IPPROTO_ESP: int
+IPPROTO_FRAGMENT: int
+IPPROTO_GGP: int
+IPPROTO_GRE: int
+IPPROTO_HELLO: int
+IPPROTO_HOPOPTS: int
+IPPROTO_ICMP: int
+IPPROTO_ICMPV6: int
+IPPROTO_IDP: int
+IPPROTO_IGMP: int
+IPPROTO_IP: int
+IPPROTO_IPCOMP: int
+IPPROTO_IPIP: int
+IPPROTO_IPV4: int
+IPPROTO_IPV6: int
+IPPROTO_MAX: int
+IPPROTO_MOBILE: int
+IPPROTO_ND: int
+IPPROTO_NONE: int
+IPPROTO_PIM: int
+IPPROTO_PUP: int
+IPPROTO_RAW: int
+IPPROTO_ROUTING: int
+IPPROTO_RSVP: int
+IPPROTO_SCTP: int
+IPPROTO_TCP: int
+IPPROTO_TP: int
+IPPROTO_UDP: int
+IPPROTO_VRRP: int
+IPPROTO_XTP: int
+IPV6_CHECKSUM: int
+IPV6_DONTFRAG: int
+IPV6_DSTOPTS: int
+IPV6_HOPLIMIT: int
+IPV6_HOPOPTS: int
+IPV6_JOIN_GROUP: int
+IPV6_LEAVE_GROUP: int
+IPV6_MULTICAST_HOPS: int
+IPV6_MULTICAST_IF: int
+IPV6_MULTICAST_LOOP: int
+IPV6_NEXTHOP: int
+IPV6_PATHMTU: int
+IPV6_PKTINFO: int
+IPV6_RECVDSTOPTS: int
+IPV6_RECVHOPLIMIT: int
+IPV6_RECVHOPOPTS: int
+IPV6_RECVPATHMTU: int
+IPV6_RECVPKTINFO: int
+IPV6_RECVRTHDR: int
+IPV6_RECVTCLASS: int
+IPV6_RTHDR: int
+IPV6_RTHDR_TYPE_0: int
+IPV6_RTHDRDSTOPTS: int
+IPV6_TCLASS: int
+IPV6_UNICAST_HOPS: int
+IPV6_USE_MIN_MTU: int
+IPV6_V6ONLY: int
+IP_ADD_MEMBERSHIP: int
+IP_DEFAULT_MULTICAST_LOOP: int
+IP_DEFAULT_MULTICAST_TTL: int
+IP_DROP_MEMBERSHIP: int
+IP_HDRINCL: int
+IP_MAX_MEMBERSHIPS: int
+IP_MULTICAST_IF: int
+IP_MULTICAST_LOOP: int
+IP_MULTICAST_TTL: int
+IP_OPTIONS: int
+IP_RECVDSTADDR: int
+IP_RECVOPTS: int
+IP_RECVRETOPTS: int
+IP_RETOPTS: int
+IP_TOS: int
+IP_TRANSPARENT: int
+IP_TTL: int
+IPX_TYPE: int
+LOCAL_PEERCRED: int
+MSG_BCAST: int
+MSG_BTAG: int
+MSG_CMSG_CLOEXEC: int
+MSG_CONFIRM: int
+MSG_CTRUNC: int
+MSG_DONTROUTE: int
+MSG_DONTWAIT: int
+MSG_EOF: int
+MSG_EOR: int
+MSG_ERRQUEUE: int
+MSG_ETAG: int
+MSG_FASTOPEN: int
+MSG_MCAST: int
+MSG_MORE: int
+MSG_NOSIGNAL: int
+MSG_NOTIFICATION: int
+MSG_OOB: int
+MSG_PEEK: int
+MSG_TRUNC: int
+MSG_WAITALL: int
+NETLINK_ARPD: int
+NETLINK_CRYPTO: int
+NETLINK_DNRTMSG: int
+NETLINK_FIREWALL: int
+NETLINK_IP6_FW: int
+NETLINK_NFLOG: int
+NETLINK_ROUTE6: int
+NETLINK_ROUTE: int
+NETLINK_SKIP: int
+NETLINK_TAPBASE: int
+NETLINK_TCPDIAG: int
+NETLINK_USERSOCK: int
+NETLINK_W1: int
+NETLINK_XFRM: int
+NI_DGRAM: int
+NI_MAXHOST: int
+NI_MAXSERV: int
+NI_NAMEREQD: int
+NI_NOFQDN: int
+NI_NUMERICHOST: int
+NI_NUMERICSERV: int
+PACKET_BROADCAST: int
+PACKET_FASTROUTE: int
+PACKET_HOST: int
+PACKET_LOOPBACK: int
+PACKET_MULTICAST: int
+PACKET_OTHERHOST: int
+PACKET_OUTGOING: int
+PF_CAN: int
+PF_PACKET: int
+PF_RDS: int
+PF_SYSTEM: int
+SCM_CREDENTIALS: int
+SCM_CREDS: int
+SCM_RIGHTS: int
+SHUT_RD: int
+SHUT_RDWR: int
+SHUT_WR: int
+SOL_ATALK: int
+SOL_AX25: int
+SOL_CAN_BASE: int
+SOL_CAN_RAW: int
+SOL_HCI: int
+SOL_IP: int
+SOL_IPX: int
+SOL_NETROM: int
+SOL_RDS: int
+SOL_ROSE: int
+SOL_SOCKET: int
+SOL_TCP: int
+SOL_TIPC: int
+SOL_UDP: int
+SO_ACCEPTCONN: int
+SO_BINDTODEVICE: int
+SO_BROADCAST: int
+SO_DEBUG: int
+SO_DONTROUTE: int
+SO_ERROR: int
+SO_EXCLUSIVEADDRUSE: int
+SO_KEEPALIVE: int
+SO_LINGER: int
+SO_MARK: int
+SO_OOBINLINE: int
+SO_PASSCRED: int
+SO_PEERCRED: int
+SO_PRIORITY: int
+SO_RCVBUF: int
+SO_RCVLOWAT: int
+SO_RCVTIMEO: int
+SO_REUSEADDR: int
+SO_REUSEPORT: int
+SO_SETFIB: int
+SO_SNDBUF: int
+SO_SNDLOWAT: int
+SO_SNDTIMEO: int
+SO_TYPE: int
+SO_USELOOPBACK: int
+SYSPROTO_CONTROL: int
+TCP_CORK: int
+TCP_DEFER_ACCEPT: int
+TCP_FASTOPEN: int
+TCP_INFO: int
+TCP_KEEPCNT: int
+TCP_KEEPIDLE: int
+TCP_KEEPINTVL: int
+TCP_LINGER2: int
+TCP_MAXSEG: int
+TCP_NODELAY: int
+TCP_NOTSENT_LOWAT: int
+TCP_QUICKACK: int
+TCP_SYNCNT: int
+TCP_WINDOW_CLAMP: int
+TIPC_ADDR_ID: int
+TIPC_ADDR_NAME: int
+TIPC_ADDR_NAMESEQ: int
+TIPC_CFG_SRV: int
+TIPC_CLUSTER_SCOPE: int
+TIPC_CONN_TIMEOUT: int
+TIPC_CRITICAL_IMPORTANCE: int
+TIPC_DEST_DROPPABLE: int
+TIPC_HIGH_IMPORTANCE: int
+TIPC_IMPORTANCE: int
+TIPC_LOW_IMPORTANCE: int
+TIPC_MEDIUM_IMPORTANCE: int
+TIPC_NODE_SCOPE: int
+TIPC_PUBLISHED: int
+TIPC_SRC_DROPPABLE: int
+TIPC_SUB_CANCEL: int
+TIPC_SUB_PORTS: int
+TIPC_SUB_SERVICE: int
+TIPC_SUBSCR_TIMEOUT: int
+TIPC_TOP_SRV: int
+TIPC_WAIT_FOREVER: int
+TIPC_WITHDRAWN: int
+TIPC_ZONE_SCOPE: int
 
-# the following constants are included with Python 3.2.3 (Ubuntu)
-# some of the constants may be Linux-only
-# all Windows/Mac-specific constants are absent
-AF_APPLETALK = 0
-AF_ASH = 0
-AF_ATMPVC = 0
-AF_ATMSVC = 0
-AF_AX25 = 0
-AF_BLUETOOTH = 0
-AF_BRIDGE = 0
-AF_DECnet = 0
-AF_ECONET = 0
-AF_IPX = 0
-AF_IRDA = 0
-AF_KEY = 0
-AF_LLC = 0
-AF_NETBEUI = 0
-AF_NETLINK = 0
-AF_NETROM = 0
-AF_PACKET = 0
-AF_PPPOX = 0
-AF_ROSE = 0
-AF_ROUTE = 0
-AF_SECURITY = 0
-AF_SNA = 0
-AF_TIPC = 0
-AF_UNSPEC = 0
-AF_WANPIPE = 0
-AF_X25 = 0
-AI_ADDRCONFIG = 0
-AI_ALL = 0
-AI_CANONNAME = 0
-AI_NUMERICHOST = 0
-AI_NUMERICSERV = 0
-AI_PASSIVE = 0
-AI_V4MAPPED = 0
-BDADDR_ANY = 0
-BDADDR_LOCAL = 0
-BTPROTO_HCI = 0
-BTPROTO_L2CAP = 0
-BTPROTO_RFCOMM = 0
-BTPROTO_SCO = 0
-CAPI = 0
-EAGAIN = 0
-EAI_ADDRFAMILY = 0
-EAI_AGAIN = 0
-EAI_BADFLAGS = 0
-EAI_FAIL = 0
-EAI_FAMILY = 0
-EAI_MEMORY = 0
-EAI_NODATA = 0
-EAI_NONAME = 0
-EAI_OVERFLOW = 0
-EAI_SERVICE = 0
-EAI_SOCKTYPE = 0
-EAI_SYSTEM = 0
-EBADF = 0
-EINTR = 0
-EWOULDBLOCK = 0
-HCI_DATA_DIR = 0
-HCI_FILTER = 0
-HCI_TIME_STAMP = 0
-INADDR_ALLHOSTS_GROUP = 0
-INADDR_ANY = 0
-INADDR_BROADCAST = 0
-INADDR_LOOPBACK = 0
-INADDR_MAX_LOCAL_GROUP = 0
-INADDR_NONE = 0
-INADDR_UNSPEC_GROUP = 0
-IPPORT_RESERVED = 0
-IPPORT_USERRESERVED = 0
-IPPROTO_AH = 0
-IPPROTO_DSTOPTS = 0
-IPPROTO_EGP = 0
-IPPROTO_ESP = 0
-IPPROTO_FRAGMENT = 0
-IPPROTO_GRE = 0
-IPPROTO_HOPOPTS = 0
-IPPROTO_ICMP = 0
-IPPROTO_ICMPV6 = 0
-IPPROTO_IDP = 0
-IPPROTO_IGMP = 0
-IPPROTO_IP = 0
-IPPROTO_IPIP = 0
-IPPROTO_IPV6 = 0
-IPPROTO_NONE = 0
-IPPROTO_PIM = 0
-IPPROTO_PUP = 0
-IPPROTO_RAW = 0
-IPPROTO_ROUTING = 0
-IPPROTO_RSVP = 0
-IPPROTO_TCP = 0
-IPPROTO_TP = 0
-IPPROTO_UDP = 0
-IPV6_CHECKSUM = 0
-IPV6_DSTOPTS = 0
-IPV6_HOPLIMIT = 0
-IPV6_HOPOPTS = 0
-IPV6_JOIN_GROUP = 0
-IPV6_LEAVE_GROUP = 0
-IPV6_MULTICAST_HOPS = 0
-IPV6_MULTICAST_IF = 0
-IPV6_MULTICAST_LOOP = 0
-IPV6_NEXTHOP = 0
-IPV6_PKTINFO = 0
-IPV6_RECVDSTOPTS = 0
-IPV6_RECVHOPLIMIT = 0
-IPV6_RECVHOPOPTS = 0
-IPV6_RECVPKTINFO = 0
-IPV6_RECVRTHDR = 0
-IPV6_RECVTCLASS = 0
-IPV6_RTHDR = 0
-IPV6_RTHDRDSTOPTS = 0
-IPV6_RTHDR_TYPE_0 = 0
-IPV6_TCLASS = 0
-IPV6_UNICAST_HOPS = 0
-IPV6_V6ONLY = 0
-IP_ADD_MEMBERSHIP = 0
-IP_DEFAULT_MULTICAST_LOOP = 0
-IP_DEFAULT_MULTICAST_TTL = 0
-IP_DROP_MEMBERSHIP = 0
-IP_HDRINCL = 0
-IP_MAX_MEMBERSHIPS = 0
-IP_MULTICAST_IF = 0
-IP_MULTICAST_LOOP = 0
-IP_MULTICAST_TTL = 0
-IP_OPTIONS = 0
-IP_RECVOPTS = 0
-IP_RECVRETOPTS = 0
-IP_RETOPTS = 0
-IP_TOS = 0
-IP_TTL = 0
-MSG_CTRUNC = 0
-MSG_DONTROUTE = 0
-MSG_DONTWAIT = 0
-MSG_EOR = 0
-MSG_OOB = 0
-MSG_PEEK = 0
-MSG_TRUNC = 0
-MSG_WAITALL = 0
-NETLINK_DNRTMSG = 0
-NETLINK_FIREWALL = 0
-NETLINK_IP6_FW = 0
-NETLINK_NFLOG = 0
-NETLINK_ROUTE = 0
-NETLINK_USERSOCK = 0
-NETLINK_XFRM = 0
-NI_DGRAM = 0
-NI_MAXHOST = 0
-NI_MAXSERV = 0
-NI_NAMEREQD = 0
-NI_NOFQDN = 0
-NI_NUMERICHOST = 0
-NI_NUMERICSERV = 0
-PACKET_BROADCAST = 0
-PACKET_FASTROUTE = 0
-PACKET_HOST = 0
-PACKET_LOOPBACK = 0
-PACKET_MULTICAST = 0
-PACKET_OTHERHOST = 0
-PACKET_OUTGOING = 0
-PF_PACKET = 0
-SHUT_RD = 0
-SHUT_RDWR = 0
-SHUT_WR = 0
-SOL_HCI = 0
-SOL_IP = 0
-SOL_SOCKET = 0
-SOL_TCP = 0
-SOL_TIPC = 0
-SOL_UDP = 0
-SO_ACCEPTCONN = 0
-SO_BROADCAST = 0
-SO_DEBUG = 0
-SO_DONTROUTE = 0
-SO_ERROR = 0
-SO_KEEPALIVE = 0
-SO_LINGER = 0
-SO_OOBINLINE = 0
-SO_RCVBUF = 0
-SO_RCVLOWAT = 0
-SO_RCVTIMEO = 0
-SO_REUSEADDR = 0
-SO_SNDBUF = 0
-SO_SNDLOWAT = 0
-SO_SNDTIMEO = 0
-SO_TYPE = 0
-TCP_CORK = 0
-TCP_DEFER_ACCEPT = 0
-TCP_INFO = 0
-TCP_KEEPCNT = 0
-TCP_KEEPIDLE = 0
-TCP_KEEPINTVL = 0
-TCP_LINGER2 = 0
-TCP_MAXSEG = 0
-TCP_NODELAY = 0
-TCP_QUICKACK = 0
-TCP_SYNCNT = 0
-TCP_WINDOW_CLAMP = 0
-TIPC_ADDR_ID = 0
-TIPC_ADDR_NAME = 0
-TIPC_ADDR_NAMESEQ = 0
-TIPC_CFG_SRV = 0
-TIPC_CLUSTER_SCOPE = 0
-TIPC_CONN_TIMEOUT = 0
-TIPC_CRITICAL_IMPORTANCE = 0
-TIPC_DEST_DROPPABLE = 0
-TIPC_HIGH_IMPORTANCE = 0
-TIPC_IMPORTANCE = 0
-TIPC_LOW_IMPORTANCE = 0
-TIPC_MEDIUM_IMPORTANCE = 0
-TIPC_NODE_SCOPE = 0
-TIPC_PUBLISHED = 0
-TIPC_SRC_DROPPABLE = 0
-TIPC_SUBSCR_TIMEOUT = 0
-TIPC_SUB_CANCEL = 0
-TIPC_SUB_PORTS = 0
-TIPC_SUB_SERVICE = 0
-TIPC_TOP_SRV = 0
-TIPC_WAIT_FOREVER = 0
-TIPC_WITHDRAWN = 0
-TIPC_ZONE_SCOPE = 0
+if sys.version_info >= (3, 3):
+    RDS_CANCEL_SENT_TO: int
+    RDS_CMSG_RDMA_ARGS: int
+    RDS_CMSG_RDMA_DEST: int
+    RDS_CMSG_RDMA_MAP: int
+    RDS_CMSG_RDMA_STATUS: int
+    RDS_CMSG_RDMA_UPDATE: int
+    RDS_CONG_MONITOR: int
+    RDS_FREE_MR: int
+    RDS_GET_MR: int
+    RDS_GET_MR_FOR_DEST: int
+    RDS_RDMA_DONTWAIT: int
+    RDS_RDMA_FENCE: int
+    RDS_RDMA_INVALIDATE: int
+    RDS_RDMA_NOTIFY_ME: int
+    RDS_RDMA_READWRITE: int
+    RDS_RDMA_SILENT: int
+    RDS_RDMA_USE_ONCE: int
+    RDS_RECVERR: int
 
+if sys.version_info >= (3, 4):
+    CAN_BCM: int
+    CAN_BCM_TX_SETUP: int
+    CAN_BCM_TX_DELETE: int
+    CAN_BCM_TX_READ: int
+    CAN_BCM_TX_SEND: int
+    CAN_BCM_RX_SETUP: int
+    CAN_BCM_RX_DELETE: int
+    CAN_BCM_RX_READ: int
+    CAN_BCM_TX_STATUS: int
+    CAN_BCM_TX_EXPIRED: int
+    CAN_BCM_RX_STATUS: int
+    CAN_BCM_RX_TIMEOUT: int
+    CAN_BCM_RX_CHANGED: int
+    AF_LINK: int
+
+if sys.version_info >= (3, 5):
+    CAN_RAW_FD_FRAMES: int
+
+if sys.version_info >= (3, 6):
+    SO_DOMAIN: int
+    SO_PROTOCOL: int
+    SO_PEERSEC: int
+    SO_PASSSEC: int
+    TCP_USER_TIMEOUT: int
+    TCP_CONGESTION: int
+    AF_ALG: int
+    SOL_ALG: int
+    ALG_SET_KEY: int
+    ALG_SET_IV: int
+    ALG_SET_OP: int
+    ALG_SET_AEAD_ASSOCLEN: int
+    ALG_SET_AEAD_AUTHSIZE: int
+    ALG_SET_PUBKEY: int
+    ALG_OP_DECRYPT: int
+    ALG_OP_ENCRYPT: int
+    ALG_OP_SIGN: int
+    ALG_OP_VERIFY: int
+
+if sys.platform == 'win32':
+    SIO_RCVALL: int
+    SIO_KEEPALIVE_VALS: int
+    RCVALL_IPLEVEL: int
+    RCVALL_MAX: int
+    RCVALL_OFF: int
+    RCVALL_ON: int
+    RCVALL_SOCKETLEVELONLY: int
+
+    if sys.version_info >= (3, 6):
+        SIO_LOOPBACK_FAST_PATH: int
 
 # enum versions of above flags py 3.4+
 if sys.version_info >= (3, 4):
@@ -285,6 +438,7 @@ if sys.version_info >= (3, 4):
         AF_UNSPEC = ...
         AF_WANPIPE = ...
         AF_X25 = ...
+        AF_LINK = ...
 
     class SocketKind(IntEnum):
         SOCK_STREAM = ...
@@ -340,9 +494,9 @@ class timeout(error):
 
 # ----- classes -----
 class socket:
-    family = 0
-    type = 0
-    proto = 0
+    family: int
+    type: int
+    proto: int
 
     if sys.version_info < (3,):
         def __init__(self, family: int = ..., type: int = ...,