Peter Simons wrote:
I have tried to use the various POpen-like implementations out there, but _none_ of them works with the most current GHC. Is there any way to communicate with external programs at the moment? Posix-only would be suffice at the moment.
There's the DIY solution, i.e. a direct translation of how popen() is implemented in C, e.g.:
module Main where
import IO import System import System.Posix
main = do (rfd, wfd) <- createPipe pid <- forkProcess (proc rfd wfd) closeFd wfd hRead <- fdToHandle rfd str <- hGetContents hRead putStr str stat <- getProcessStatus True False pid case stat of (Just (Exited code)) -> exitWith code _ -> exitWith (ExitFailure 127) where proc rfd wfd = do closeFd rfd dupTo wfd stdOutput executeFile "/bin/ls" False ["-l"] Nothing
The above has been (briefly) tested with ghc 6.2.1.
--
Glynn Clements