Thank you.
Pierre
On Fri, 25 Aug 2000, John Peterson wrote:
> The problem is that readFile is lazy - it doesn't read the characters
> at the time of readFile but rather as they are needed. If you write
> to a different file there's no problem. In general, you have to be
> careful not to use the file opened by readFile in other IO unless
> you're sure you are finished with it. A simple way to get around this
> is to use a strict functlon like == to force the entire file contents:
>
> x <- readFile f
> if x == x then writeFile f (x ++ "more") else return ()
>
> John
>
