System.Posix.IO.ByteString fdRead and fdWrite.

Herbert Valerio Riedel hvr at
Thu Nov 21 08:18:10 UTC 2013

On 2013-11-21 at 00:03:46 +0100, Ashley Yakeley wrote:
> In unix-, fdRead and fdWrite in System.Posix.IO.ByteString use
> String instead of ByteString. This is wrong, isn't it? The point of
> the .ByteString modules is to do IO in ByteString.

Fwiw, here's the commit introducing the ByteString API and stating its intention:

However, I'm not totally sure from that, whether the type-sigs

 fdRead :: Fd
        -> ByteCount -- ^How many bytes to read
        -> IO (String, ByteCount) -- ^ The bytes read, how many bytes were read.

 fdWrite :: Fd -> String -> IO ByteCount

were really intended to be that way. 

Simon, maybe you can provide some insight here?


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