Hi, I wanted to see if anyone had an idea about why the following program results in an exception. The issue seems to be related to stdin to a POSIX file descriptors for a subprocess, and GHC's Unicode encoding lookup. I've tried to make the program as simple as possible to make the issue obvious. Consider:

module Pipe where

import System.Process import System.IO import System.Posix.IO

main = sequence_ $ replicate 100000 f

f = do (Just hin, _, _, prc) <- createProcess (shell "./pipe_c.out") { std_in = CreatePipe , std_out = UseHandle stdout , std_err = UseHandle stderr}

pin <- handleToFd hin _ <- fdWrite pin ("h\n") closeFd pin waitForProcess prc

and a trivial C program to read in the data (but doing nothing with it): --------------------------------------- #include #define SIZE 10 int main(void) { char in[SIZE]; if(fgets(in, SIZE , stdin) != NULL); return 0; } ---------------------------------------- and executing

gcc -Wall -o pipe_c.out pipe_c.c ghci Pipe.hs main ... *** Exception: malloc: resource exhausted (out of memory) iconvOpen ("UTF-8","UTF-8"): resource exhausted (Cannot allocate memory)

My best guess is that the GHC is calling iconv_open() http://www.kernel.org/doc/man-pages/online/pages/man3/iconv_open.3.html, but not making a subsequent call to iconv_close() http://www.kernel.org/doc/man-pages/online/pages/man3/iconv_close.3.html. (Actually, my best guess is I'm making a silly mistake, but I'm having trouble seeing it. :) ) I am running 2.6.35-28-generic (Ubuntu) and GHC 7.0.2, but I've observed the same issues with GHC 6.12.3. Lee