| Safe Haskell | Safe |
|---|---|
| Language | Haskell2010 |
Bio.Iteratee.IO.Base
- type FileOffset = COff
- myfdRead :: Fd -> Ptr CChar -> ByteCount -> IO (Either Errno ByteCount)
- myfdSeek :: Fd -> SeekMode -> FileOffset -> IO (Either Errno FileOffset)
- newtype Errno :: * = Errno CInt
- select'read'pending :: [Fd] -> IO (Either Errno [Fd])
Documentation
type FileOffset = COff
myfdRead :: Fd -> Ptr CChar -> ByteCount -> IO (Either Errno ByteCount) Source
Alas, GHC provides no function to read from Fd to an allocated buffer. The library function fdRead is not appropriate as it returns a string already. I'd rather get data from a buffer. Furthermore, fdRead (at least in GHC) allocates a new buffer each time it is called. This is a waste. Yet another problem with fdRead is in raising an exception on any IOError or even EOF. I'd rather avoid exceptions altogether.
myfdSeek :: Fd -> SeekMode -> FileOffset -> IO (Either Errno FileOffset) Source
The following fseek procedure throws no exceptions.
select'read'pending :: [Fd] -> IO (Either Errno [Fd]) Source
poll if file descriptors have something to read Return the list of read-pending descriptors