Ahn, Ki Yung wrote:
What I mean by getCh is the non-buffered non-echoed version of getChar, which Hugs used to provided as an extension but not any more.
Is there any way to have a non-buffered non-echoed single character input function on MS Windows command line using only the libraries in the MS Windows distribution packages of either GHC or Hugs?
The reason to why this is important for me is because I am translating Graham Hutton's "Programming in Haskell" into Korean (soon to be published), which illustrates interactive programming with the example of a calculator that responds instantly for every keystroke of numbers and arithmetic operations running on text mode. It is very important to consider the readers who only have access to MS Windows systems, because Korean OS market share is completely skewed towards MS Windows for very embarrassing reasons that I do not even want to mention. And, isn't GHC developed in MSR anyway? :-)
I remember that this is an old problem for both of the two most widely used Haskell implementation, Hugs and GHC.
In ghc 6.8 getChar had a bit strange behavior. As far as I remember it always worked as if it were NoBuffering. Fortunately, in the recently released ghc 6.10, this has been fixed. We now actually have to set the buffering mode to NoBuffering with hSetBufferring to get the non-buffered behavior of getChar. But, it still isn't working on MS Windows.
Here's the ticket: http://hackage.haskell.org/trac/ghc/ticket/2189 This needs somebody familiar with the intricacies of Windows Consoles to fix. Any takers? Cheers, Simon