Modulesemaphore-compat-2.0.1Haskell2010

System.Semaphore.Internal.DomainSocket

FFI glue code for Unix domain sockets.

1 type
6 values

Packagesemaphore-compat-2.0.1
Exports7
LanguageHaskell2010
LicenceBSD-3-Clause
SourceDomainSocket.hs

valueconnectDomainSocket :: FilePath -> IO Fd

valuelistenDomainSocket :: FilePath -> IO Fd

Open a socket in non blocking mode (O_NONBLOCK)

valuepollAcceptSocket :: Fd -> Fd -> IO AcceptResult

Block until either a client connects or the cancel fd is written to.

Relies on cooperative cancellation implemented in hs_poll_accept using poll(2) + accept(2) via safe FFI to avoid GHC #27110 and #27113.

Must be called from a masked context. The caller is responsible for installing an exception handler that closes all 3 fds (inputs and outputs).

datadata AcceptResult

Result of pollAcceptSocket.

Constructors

AcceptedFd !Fd
A client connected; here is the fd.
AcceptCancelled
The cancel pipe was signalled.

valuefdReadByte :: HasCallStack => Fd -> IO Word8

Read a single byte from a file descriptor. Throws an EOF IOError if the peer has disconnected.

valuefdWriteByte :: HasCallStack => Fd -> Word8 -> IO ()

Write a single byte to a file descriptor.

valuefdShutdown :: Fd -> IO ()

Shut down a socket for both reading and writing. A concurrent fdReadByte on the same fd will return immediately Used to cancel threads blocked in read()