Hello! I am trying to find out the way of uploading a file using HTTP multipart/form-data. I created simple application aimed to upload an image to imgpaste.com. The source is below: ========================================================= module ImgPaste.Upload where import Control.Monad import Network.Curl import Data.ByteString import Text.Regex.PCRE import Text.Regex.PCRE.ByteString type LocalCtx = ( ByteString, ByteString, ByteString, [ByteString] ) type UploadResult = Either UploadError ByteString data UploadError = UploadError {    message :: String,    response :: ByteString } deriving (Show) extractResponse :: CurlResponse_ [(String,String)] ByteString -> ByteString extractResponse = respBody uploadFile :: String -> IO (ByteString) uploadFile fileName = initialize >>= withCurlDo . (flip uploadFileWithCurl fileName) uploadFileWithCurl :: Curl -> String -> IO ( ByteString ) uploadFileWithCurl curl fileName = do    liftM extractResponse $ do_curl_ curl "http://imgpaste.com/"        [CurlPost True, CurlHttpPost postData, CurlVerbose True ]    where        postData = [            HttpPost "upfile"                Nothing                ( ContentFile fileName )                []                Nothing,            makeFormPost "submit" "Upload",            makeFormPost "keep" "a"            ]        makeFormPost name value = HttpPost name Nothing            (ContentString value)            []            Nothing -- <input type="text" name="copyfield" size="31" value="http://imgpaste.com/tmp/123456.png" /> extractUrl :: ByteString -> UploadResult extractUrl src = match (src =~ "" :: LocalCtx)    where        match (_,_,_,[x]) = Right x        match _ = Left $ UploadError "Can not parse content." src pasteImage :: String -> IO ( UploadResult ) pasteImage = liftM extractUrl . uploadFile ========================================================= however when invoking the function: pasteImage "image.png" no data is posted to the server. The protocol dump looks like: ========================================================= POST / HTTP/1.1 Host: imgpaste.com Accept: */* Content-Length: 241 Expect: 100-continue Content-Type: multipart/form-data; boundary=----------------------------630d154aaf3b ========================================================= so the request data is not sent. Can somebody please advice, what am I doing in a wrong way? Thank you in advance! -- regards Eugene Dzhurinsky