System.Posix.IO.Select.Types

Various types.

Documentation

data Timeout

A timeout of Never tells select(2) to never time out, while Time sets a finite timeout.

Constructors

Never

Time CTimeval

data CTimeval

A Storable instance for struct timeval (see select(2)). The first argument corresponds to tv_sec, the second to tv_usec.

Constructors

CTimeval CLong CLong

Instances

Storable CTimeval

finite :: CLong -> CLong -> Timeout

finite s us tells select to time out after s seconds and us microseconds.

data Result

Abstraction for the return value of select. Error means that select returned an error, while Timeout means it timed out. Ready n rfds wfds efds specifies that it returned because the file descriptors in rfds, wfds and efds are ready in their respective ways (see select(2)), with n descriptors in total.

Constructors

Error

Timeout

Ready CInt FdSet FdSet FdSet

numReady :: Result -> CInt

The total number of ready file descriptors across all three sets.

readyRead :: Result -> FdSet

The file descriptors ready for reading.

readyWrite :: Result -> FdSet

The file descriptors ready for writing.

readyException :: Result -> FdSet

The file descriptors having exceptional conditions.