This module implements a low-level cross-platform sockets interface. Look at the net module for the higher-level version.
Types
Port = distinct uint16
- port type Source Edit
Domain = enum AF_UNIX, ## for local socket (using a file). Unsupported on Windows. AF_INET = 2, ## for network protocol IPv4 or AF_INET6 = 23 ## for network protocol IPv6.
- domain, which specifies the protocol family of the created socket. Other domains than those that are listed here are unsupported. Source Edit
SockType = enum SOCK_STREAM = 1, ## reliable stream-oriented service or Stream Sockets SOCK_DGRAM = 2, ## datagram service or Datagram Sockets SOCK_RAW = 3, ## raw protocols atop the network layer. SOCK_SEQPACKET = 5 ## reliable sequenced packet service
- second argument to socket proc Source Edit
Protocol = enum IPPROTO_TCP = 6, ## Transmission control protocol. IPPROTO_UDP = 17, ## User datagram protocol. IPPROTO_IP, ## Internet protocol. Unsupported on Windows. IPPROTO_IPV6, ## Internet Protocol Version 6. Unsupported on Windows. IPPROTO_RAW, ## Raw IP Packets Protocol. Unsupported on Windows. IPPROTO_ICMP ## Control message protocol. Unsupported on Windows.
- third argument to socket proc Source Edit
Servent = object name*: string aliases*: seq[string] port*: Port proto*: string
- information about a service Source Edit
Hostent = object name*: string aliases*: seq[string] addrtype*: Domain length*: int addrList*: seq[string]
- information about a given host Source Edit
Procs
proc ioctlsocket(s: SocketHandle; cmd: clong; argptr: ptr clong): cint {.
stdcall, importc: "ioctlsocket", dynlib: "ws2_32.dll".}- Source Edit
proc `==`(a, b: Port): bool {.
borrow.}- == for ports. Source Edit
proc `$`(p: Port): string {.
borrow.}- returns the port number as a string Source Edit
proc toInt(domain: Domain): cint {.
raises: [], tags: [].}- Converts the Domain enum to a platform-dependent cint. Source Edit
proc toInt(typ: SockType): cint {.
raises: [], tags: [].}- Converts the SockType enum to a platform-dependent cint. Source Edit
proc toInt(p: Protocol): cint {.
raises: [], tags: [].}- Converts the Protocol enum to a platform-dependent cint. Source Edit
proc newNativeSocket(domain: Domain = AF_INET; sockType: SockType = SOCK_STREAM; protocol: Protocol = IPPROTO_TCP): SocketHandle {.
raises: [], tags: [].}- Creates a new socket; returns InvalidSocket if an error occurs. Source Edit
proc newNativeSocket(domain: cint; sockType: cint; protocol: cint): SocketHandle {.
raises: [], tags: [].}-
Creates a new socket; returns InvalidSocket if an error occurs.
Use this overload if one of the enums specified above does not contain what you need.
Source Edit proc close(socket: SocketHandle) {.
raises: [], tags: [].}- closes a socket. Source Edit
proc bindAddr(socket: SocketHandle; name: ptr SockAddr; namelen: SockLen): cint {.
raises: [], tags: [].}- Source Edit
proc listen(socket: SocketHandle; backlog = SOMAXCONN): cint {.
tags: [ReadIOEffect], raises: [].}- Marks socket as accepting connections. Backlog specifies the maximum length of the queue of pending connections. Source Edit
proc getAddrInfo(address: string; port: Port; domain: Domain = AF_INET; sockType: SockType = SOCK_STREAM; protocol: Protocol = IPPROTO_TCP): ptr AddrInfo {.
raises: [OSError], tags: [].}-
Source EditWarning: The resulting ptr TAddrInfo must be freed using dealloc!
proc dealloc(ai: ptr AddrInfo) {.
raises: [], tags: [].}- Source Edit
proc ntohl(x: uint32): uint32 {.
raises: [], tags: [].}- Converts 32-bit unsigned integers from network to host byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 4-byte swap operation. Source Edit
proc ntohs(x: uint16): uint16 {.
raises: [], tags: [].}- Converts 16-bit unsigned integers from network to host byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 2-byte swap operation. Source Edit
proc getServByName(name, proto: string): Servent {.
tags: [ReadIOEffect], raises: [OSError].}-
Searches the database from the beginning and finds the first entry for which the service name specified by name matches the s_name member and the protocol name specified by proto matches the s_proto member.
On posix this will search through the /etc/services file.
Source Edit proc getServByPort(port: Port; proto: string): Servent {.
tags: [ReadIOEffect], raises: [OSError].}-
Searches the database from the beginning and finds the first entry for which the port specified by port matches the s_port member and the protocol name specified by proto matches the s_proto member.
On posix this will search through the /etc/services file.
Source Edit proc getHostByAddr(ip: string): Hostent {.
tags: [ReadIOEffect], raises: [OSError].}- This function will lookup the hostname of an IP Address. Source Edit
proc getHostByName(name: string): Hostent {.
tags: [ReadIOEffect], raises: [OSError].}- This function will lookup the IP address of a hostname. Source Edit
proc getSockDomain(socket: SocketHandle): Domain {.
raises: [OSError], tags: [].}- returns the socket's domain (AF_INET or AF_INET6). Source Edit
proc getAddrString(sockAddr: ptr SockAddr): string {.
raises: [OSError], tags: [].}- return the string representation of address within sockAddr Source Edit
proc getSockName(socket: SocketHandle): Port {.
raises: [OSError], tags: [].}- returns the socket's associated port number. Source Edit
proc getLocalAddr(socket: SocketHandle; domain: Domain): (string, Port) {.
raises: [OSError, Exception], tags: [RootEffect].}-
returns the socket's local address and port number.
Similar to POSIX's getsockname.
Source Edit proc getPeerAddr(socket: SocketHandle; domain: Domain): (string, Port) {.
raises: [OSError, Exception], tags: [RootEffect].}-
returns the socket's peer address and port number.
Similar to POSIX's getpeername
Source Edit proc getSockOptInt(socket: SocketHandle; level, optname: int): int {.
tags: [ReadIOEffect], raises: [OSError].}- getsockopt for integer options. Source Edit
proc setSockOptInt(socket: SocketHandle; level, optname, optval: int) {.
tags: [WriteIOEffect], raises: [OSError].}- setsockopt for integer options. Source Edit
proc setBlocking(s: SocketHandle; blocking: bool) {.
raises: [OSError], tags: [].}-
Sets blocking mode on socket.
Raises EOS on error.
Source Edit proc select(readfds: var seq[SocketHandle]; timeout = 500): int {.
raises: [], tags: [].}-
Traditional select function. This function will return the number of sockets that are ready to be read from, written to, or which have errors. If there are none; 0 is returned. Timeout is in milliseconds and -1 can be specified for no timeout.
A socket is removed from the specific seq when it has data waiting to be read/written to or has errors (exceptfds).
Source Edit proc selectWrite(writefds: var seq[SocketHandle]; timeout = 500): int {.
tags: [ReadIOEffect], raises: [].}-
When a socket in writefds is ready to be written to then a non-zero value will be returned specifying the count of the sockets which can be written to. The sockets which can be written to will also be removed from writefds.
timeout is specified in milliseconds and -1 can be specified for an unlimited time.
Source Edit
Templates
template ntohl(x: int32): expr {.
deprecated.}- Converts 32-bit integers from network to host byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 4-byte swap operation. Warning: This template is deprecated since 0.14.0, IPv4 addresses are now treated as unsigned integers. Please use the unsigned version of this template. Source Edit
template ntohs(x: int16): expr {.
deprecated.}- Converts 16-bit integers from network to host byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 2-byte swap operation. Warning: This template is deprecated since 0.14.0, where port numbers became unsigned integers. Please use the unsigned version of this template. Source Edit
template htonl(x: int32): expr {.
deprecated.}- Converts 32-bit integers from host to network byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 4-byte swap operation. Warning: This template is deprecated since 0.14.0, IPv4 addresses are now treated as unsigned integers. Please use the unsigned version of this template. Source Edit
template htonl(x: uint32): expr
- Converts 32-bit unsigned integers from host to network byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 4-byte swap operation. Source Edit
template htons(x: int16): expr {.
deprecated.}- Converts 16-bit integers from host to network byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 2-byte swap operation. Warning: This template is deprecated since 0.14.0, where port numbers became unsigned integers. Please use the unsigned version of this template. Source Edit
template htons(x: uint16): expr
- Converts 16-bit unsigned integers from host to network byte order. On machines where the host byte order is the same as network byte order, this is a no-op; otherwise, it performs a 2-byte swap operation. Source Edit