#8844: Pseudo terminal and process-1.2.0.0 --------------------------------------+------------------------------------ Reporter: ksamborski | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: libraries/process | Version: 7.6.3 Resolution: | Keywords: pty Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: --------------------------------------+------------------------------------ Old description:

Hello,

I'm writing simple app which execute process and communicate with it via pseudo terminal. Here is some sample code:

import System.Posix.Terminal import System.Process

main = do (master, slave) <- openPseudoTerminal hslave <- fdToHandle slave hSetBuffering hslave NoBuffering (_,_,_,ph) <- createProcess (shell "mc"){ env = Just [("TERM", "xterm")] , std_in = UseHandle hslave , std_out = UseHandle hslave , std_err = UseHandle hslave , close_fds = True } forkIO $ readTerm master -- my function which reads output from process waitForProcess ph

The problem is that mc still wants some input from stdin but not from slave terminal. But when I changed function runIteractiveProcess from runProcess.c like this:

... /* Reset the SIGINT/SIGQUIT signal handlers in the child, if requested */ if (reset_int_quit_handlers) { struct sigaction dfl; (void)sigemptyset(&dfl.sa_ mask); dfl.sa_flags = 0; dfl.sa_handler = SIG_DFL; (void)sigaction(SIGINT, &dfl, NULL); (void)sigaction(SIGQUIT, &dfl, NULL); }

/********************************************************************************/ setsid(); //Make the current process a new session leader ioctl(0, TIOCSCTTY, 1); //As the child is a session leader, set the controlling terminal to be the slave side of the PTY /********************************************************************************/ /* the child */ if (environment) { // XXX Check result execvpe(args[0], args, environment); } else { // XXX Check result execvp(args[0], args); }

childFailed(forkCommunicationFds[1], forkExecFailed); ...

it worked as expected, I'm not proposing patch or solution but is there any chance to add support for pseudo terminals in the process library? Maybe just add another record field in CreateProcess like pty :: Bool and then call these two additional instructions in runIteractiveProcess?

Best regards, Karol Samborski

New description: Hello, I'm writing simple app which execute process and communicate with it via pseudo terminal. Here is some sample code: {{{#!haskell import System.Posix.Terminal import System.Process main = do (master, slave) <- openPseudoTerminal hslave <- fdToHandle slave hSetBuffering hslave NoBuffering (_,_,_,ph) <- createProcess (shell "mc"){ env = Just [("TERM", "xterm")] , std_in = UseHandle hslave , std_out = UseHandle hslave , std_err = UseHandle hslave , close_fds = True } forkIO $ readTerm master -- my function which reads output from process waitForProcess ph }}} The problem is that mc still wants some input from stdin but not from slave terminal. But when I changed function `runIteractiveProcess` from `runProcess.c` like this: {{{#!c ... /* Reset the SIGINT/SIGQUIT signal handlers in the child, if requested */ if (reset_int_quit_handlers) { struct sigaction dfl; (void)sigemptyset(&dfl.sa_ mask); dfl.sa_flags = 0; dfl.sa_handler = SIG_DFL; (void)sigaction(SIGINT, &dfl, NULL); (void)sigaction(SIGQUIT, &dfl, NULL); } /********************************************************************************/ setsid(); //Make the current process a new session leader ioctl(0, TIOCSCTTY, 1); //As the child is a session leader, set the controlling terminal to be the slave side of the PTY /********************************************************************************/ /* the child */ if (environment) { // XXX Check result execvpe(args[0], args, environment); } else { // XXX Check result execvp(args[0], args); } childFailed(forkCommunicationFds[1], forkExecFailed); ... }}} it worked as expected, I'm not proposing patch or solution but is there any chance to add support for pseudo terminals in the process library? Maybe just add another record field in `CreateProcess` like `pty :: Bool` and then call these two additional instructions in `runIteractiveProcess`? Best regards, Karol Samborski -- Comment (by hvr): improved wiki markup of description -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8844#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler