Haskell: hIsOpen: Check whether file handle is open (or) not

hIsOpen function takes a file handle and return IO True, if the handle is still in open state, else IO False.

Prelude System.IO> :t hIsOpen

hIsOpen :: Handle -> IO Bool

FileUtil.hs

import System.IO

main = do
        putStrLn "Enter file name (Including full path) to read"
        fileName <- getLine
        fileHandle <- openFile fileName ReadMode

        isHandleOpen <- hIsOpen fileHandle
        putStrLn $ "Is handle open : " ++ show isHandleOpen

        hClose fileHandle
        isHandleOpen <- hIsOpen fileHandle
        putStrLn $ "Is handle open : " ++ show isHandleOpen

$ ghc FileUtil.hs
[1 of 1] Compiling Main             ( FileUtil.hs, FileUtil.o )
Linking FileUtil ...
$
$ ./FileUtil
Enter file name (Including full path) to read
today.txt
Is handle open : True
Is handle open : False

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