Network.Socket.Internal

A module containing semi-public Socket internals. Modules which extend the Socket module will need to use this module while ideally most users will be able to make do with the public interface.

Socket addresses

type HostAddress = Word32

Network byte order.

type HostAddress6 = (Word32, Word32, Word32, Word32)

Host byte order.

type FlowInfo = Word32

type ScopeID = Word32

newtype PortNumber

Constructors

PortNum Word16

Instances

Enum PortNumber

Eq PortNumber

Integral PortNumber

Num PortNumber

Ord PortNumber

Real PortNumber

Show PortNumber

Typeable PortNumber

Storable PortNumber

data SockAddr

Constructors

SockAddrInet PortNumber HostAddress

SockAddrInet6 PortNumber FlowInfo HostAddress6 ScopeID

SockAddrUnix String

Instances

Eq SockAddr

Ord SockAddr

Show SockAddr

Typeable SockAddr

peekSockAddr :: Ptr SockAddr -> IO SockAddr

Read a SockAddr from the given memory location.

pokeSockAddr :: Ptr a -> SockAddr -> IO ()

Write the given SockAddr to the given memory location.

sizeOfSockAddr :: SockAddr -> Int

Computes the storage requirements (in bytes) of the given SockAddr. This function differs from sizeOf in that the value of the argument is used.

sizeOfSockAddrByFamily :: Family -> Int

Computes the storage requirements (in bytes) required for a SockAddr with the given Family.

withSockAddr :: SockAddr -> (Ptr SockAddr -> Int -> IO a) -> IO a

Use a SockAddr with a function requiring a pointer to a SockAddr and the length of that SockAddr.

withNewSockAddr :: Family -> (Ptr SockAddr -> Int -> IO a) -> IO a

Create a new SockAddr for use with a function requiring a pointer to a SockAddr and the length of that SockAddr.

Protocol families

data Family

Address families.

A constructor being present here does not mean it is supported by the operating system: see isSupportedFamily.

Constructors

AF_UNSPEC

AF_UNIX

AF_INET

AF_INET6

AF_IMPLINK

AF_PUP

AF_CHAOS

AF_NS

AF_NBS

AF_ECMA

AF_DATAKIT

AF_CCITT

AF_SNA

AF_DECnet

AF_DLI

AF_LAT

AF_HYLINK

AF_APPLETALK

AF_ROUTE

AF_NETBIOS

AF_NIT

AF_802

AF_ISO

AF_OSI

AF_NETMAN

AF_X25

AF_AX25

AF_OSINET

AF_GOSSIP

AF_IPX

Pseudo_AF_XTP

AF_CTF

AF_WAN

AF_SDL

AF_NETWARE

AF_NDD

AF_INTF

AF_COIP

AF_CNT

Pseudo_AF_RTIP

Pseudo_AF_PIP

AF_SIP

AF_ISDN

Pseudo_AF_KEY

AF_NATM

AF_ARP

Pseudo_AF_HDRCMPLT

AF_ENCAP

AF_LINK

AF_RAW

AF_RIF

AF_NETROM

AF_BRIDGE

AF_ATMPVC

AF_ROSE

AF_NETBEUI

AF_SECURITY

AF_PACKET

AF_ASH

AF_ECONET

AF_ATMSVC

AF_IRDA

AF_PPPOX

AF_WANPIPE

AF_BLUETOOTH

Instances

Eq Family

Ord Family

Read Family

Show Family

Socket error functions

throwSocketError

Arguments

:: String

textual description of the error location

-> IO a

Throw an IOError corresponding to the current socket error.

throwSocketErrorCode :: String -> CInt -> IO a

Like throwSocketError, but the error code is supplied as an argument.

On Windows, do not use errno. Use a system error code instead.

Guards for socket operations that may fail

throwSocketErrorIfMinus1_

Arguments

:: (Eq a, Num a)

=> String

textual description of the location

-> IO a

the IO operation to be executed

-> IO ()

Throw an IOError corresponding to the current socket error if the IO action returns a result of -1. Discards the result of the IO action after error handling.

throwSocketErrorIfMinus1Retry

Arguments

:: (Eq a, Num a)

=> String

textual description of the location

-> IO a

the IO operation to be executed

-> IO a

Throw an IOError corresponding to the current socket error if the IO action returns a result of -1, but retries in case of an interrupted operation.

throwSocketErrorIfMinus1RetryMayBlock

Arguments

:: (Eq a, Num a)

=> String

textual description of the location

-> IO b

action to execute before retrying if an immediate retry would block

-> IO a

the IO operation to be executed

-> IO a

Throw an IOError corresponding to the current socket error if the IO action returns a result of -1, but retries in case of an interrupted operation. Checks for operations that would block and executes an alternative action before retrying in that case.

Guards that wait and retry if the operation would block

These guards are based on throwSocketErrorIfMinus1RetryMayBlock. They wait for socket readiness if the action fails with EWOULDBLOCK or similar.

throwSocketErrorWaitRead :: (Eq a, Num a) => Socket -> String -> IO a -> IO a

Like throwSocketErrorIfMinus1Retry, but if the action fails with EWOULDBLOCK or similar, wait for the socket to be read-ready, and try again.

throwSocketErrorWaitWrite :: (Eq a, Num a) => Socket -> String -> IO a -> IO a

Like throwSocketErrorIfMinus1Retry, but if the action fails with EWOULDBLOCK or similar, wait for the socket to be write-ready, and try again.

Initialization

withSocketsDo :: IO a -> IO a

On Windows operating systems, the networking subsystem has to be initialised using withSocketsDo before any networking operations can be used. eg.

 main = withSocketsDo $ do {...}

Although this is only strictly necessary on Windows platforms, it is harmless on other platforms, so for portability it is good practice to use it all the time.

Low-level helpers

zeroMemory :: Ptr a -> CSize -> IO ()

Zero a structure.