I'm one bug away from a working program and need some help. I wrote a little utility that logs into LWN.net, retrieves an article, and creates an epub out of it. Full code here: git clone http://michael.orlitzky.com/git/lwn-epub.git This is the code that gets the login cookie: cj <- make_cookie_jar li_result <- log_in cj uname pword case li_result of Left err -> do let msg = "Failed to log in. " ++ err hPutStrLn stderr msg Right response_body -> do hPutStrLn stderr response_body return $ cfg { C.cookie_jar = Just cj } Curl is making the request, but if I remove the (hPutStrLn stderr response_body), it doesn't work! What's even more insane is, this works: hPutStrLn stderr response_body and this doesn't: hPutStrLn stdout response_body whaaaaaaatttttttt? I really don't want to dump the response body to stderr, but I can't even begin to imagine what's going on here. Has anyone got Network.Curl working with a cookie jar? For anyone with an LWN account: you can set, username = foo password = bar in ~/.lwn-epub/lwn-epub.conf and attempt to run with, lwn-epub -o current.epub current/bigpage