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-- !!! Testing IO.hFileSize
module Main(main) where
import Control.Monad
import System.Directory ( removeFile, doesFileExist )
import System.IO
import System.IO.Error
main = do
sz <- hFileSize stdin `catchIOError` (\ _ -> return (-1))
print sz
let fn = "hFileSize002.out"
f <- doesFileExist fn
when f (removeFile fn)
hdl <- openFile fn WriteMode
hPutStr hdl "file_size"
-- with default buffering
sz <- hFileSize hdl
print sz
hSetBuffering hdl NoBuffering
hPutStr hdl "file_size"
-- with no buffering
sz <- hFileSize hdl
print sz
hSetBuffering hdl LineBuffering
hPutStr hdl "file_size"
-- with line buffering
sz <- hFileSize hdl
print sz
hSetBuffering hdl (BlockBuffering (Just 4))
-- with block buffering
hPutStr hdl "file_size"
sz <- hFileSize hdl
print sz
hClose hdl
|
