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#514 hPutBuf doesn't respect LineBuffering

6.4
open
Simon Marlow
3
2005-09-13
2005-09-13
Simon Marlow
No

On 15 April 2005 02:39, Ian Lynagh wrote:

> If I run this program:
>
> --------------------------------------------------
> import System.Cmd (system)
> import Foreign.C.String (castCharToCChar)
> import Foreign.Marshal.Array (newArray)
> import System.IO (hSetBinaryMode, hPutBuf, stdout,
hSetBuffering,
> BufferMode(..))
>
> main = do hSetBinaryMode stdout True
> hSetBuffering stdout LineBuffering
> p <- newArray (map castCharToCChar "foo\n")
> hPutBuf stdout p 4
> system "sleep 5"
> putStr "bar\n"
> --------------------------------------------------
>
> compiled by GHC then it waits 5 seconds and then
prints foo and bar
> together.
>
> With hugs, foo is printed and then 5 seconds later
bar is printed, as
> I would expect.

True, the implementation doesn't respect LineBuffering
(though it does
respect the other buffering modes, I believe). That's
a bug.

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