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-- !!! Test file positioning
module Main(main) where
import IO
import Monad
import Directory (removeFile, doesFileExist)
main = do
hIn <- openFile "hGetPosn001.in" ReadMode
hSetBinaryMode hIn True
f <- doesFileExist "hGetPosn001.out"
when f (removeFile "hGetPosn001.out")
hOut <- openFile "hGetPosn001.out" ReadWriteMode
hSetBinaryMode hOut True
bof <- hGetPosn hIn
copy hIn hOut
hSetPosn bof
copy hIn hOut
hSeek hOut AbsoluteSeek 0
stuff <- hGetContents hOut
putStr stuff
copy :: Handle -> Handle -> IO ()
copy hIn hOut =
try (hGetChar hIn) >>=
either (\ err -> if isEOFError err then return () else error "copy")
( \ x -> hPutChar hOut x >> copy hIn hOut)
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