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Attempt to handle byte-stream in Haskell.
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| import qualified Data.ByteString as B | |
| import GHC.IO.Handle | |
| import System.Process | |
| import System.IO | |
| type Packet = B.ByteString | |
| pktsize = 188 | |
| main = do | |
| (out, err, pid) <- record "recpt1 --b25 --strip 16 100 -" | |
| outFileHdl <- makeOutputFile "out.ts" | |
| repeatIO (getAndWrite out outFileHdl) | |
| hClose outFileHdl | |
| getAndWrite :: Handle -> Handle -> IO Bool | |
| getAndWrite getHdl writeHdl = do | |
| (final, pkts) <- getAccumulatedPackets getHdl | |
| appendToFile pkts writeHdl | |
| return final | |
| repeatIO :: IO Bool -> IO () | |
| repeatIO io = do | |
| flag <- io | |
| if flag then | |
| return () | |
| else | |
| repeatIO io | |
| makeOutputFile :: FilePath -> IO Handle | |
| makeOutputFile fp = do | |
| hdl <- openFile fp WriteMode | |
| return hdl | |
| appendToFile :: [Packet] -> Handle -> IO () | |
| appendToFile pkts hdl = do | |
| B.hPut hdl (foldr B.append B.empty pkts) | |
| hFlush hdl | |
| record :: String -> IO (Handle, Handle, ProcessHandle) | |
| record command = do | |
| (inp, out, err, pid) <- runInteractiveProcess file args Nothing Nothing | |
| return (out, err, pid) | |
| where | |
| file:args = words command | |
| getAccumulatedPackets :: Handle -> IO (Bool, [Packet]) | |
| getAccumulatedPackets hdl = do | |
| bytes <- B.hGet hdl (pktsize*1000) | |
| finished <- hIsEOF hdl | |
| return (finished, splitByLength pktsize bytes) | |
| splitByLength :: Int -> B.ByteString -> [Packet] | |
| splitByLength n b | |
| | B.null b = [] | |
| | otherwise = let (pkt, rest) = B.splitAt n b in pkt:(splitByLength n rest) | |
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| import qualified Foreign.Marshal.Array as Array | |
| import qualified Data.ByteString.Lazy as B | |
| import Foreign.Ptr | |
| import Data.Word8 | |
| import GHC.IO.Handle | |
| import System.Process | |
| type Packet = B.ByteString | |
| packetsize = 188 | |
| bufsize = packetsize * 2000 | |
| main = do | |
| buf <- Array.mallocArray bufsize | |
| (out, err, pid) <- record "recpt1 --b25 --strip 16 30 -" | |
| write buf out "out.ts" | |
| write :: Ptr Word8 -> Handle -> FilePath -> IO () | |
| write buf out file = do | |
| (fin, ps) <- getNextPacket out buf | |
| B.appendFile file ps | |
| if fin then do | |
| return () | |
| else do | |
| write buf out file | |
| record :: String -> IO (Handle, Handle, ProcessHandle) | |
| record command = do | |
| (inp, out, err, pid) <- runInteractiveProcess file args Nothing Nothing | |
| return (out, err, pid) | |
| where | |
| file:args = words command | |
| getNextPacket :: Handle -> Ptr Word8 -> IO (Bool, B.ByteString) | |
| getNextPacket hdl buf = do | |
| len <- hGetBuf hdl buf bufsize | |
| ls <- Array.peekArray bufsize buf | |
| return (len /= bufsize, B.pack ls) |
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