source: owl.c @ b0430a6

/*
 * Copyright 2001 Massachusetts Institute of Technology
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that the above copyright notice and this
 * permission notice appear in all copies and in supporting
 * documentation.  No representation is made about the suitability of
 * this software for any purpose.  It is provided "as is" without
 * express or implied warranty.
 */

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "owl.h"

#if OWL_STDERR_REDIR
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#ifdef HAVE_SYS_FILIO_H
#include <sys/filio.h>
#endif
int stderr_replace(void);
void stderr_redirect(int rfd);
#endif

static const char fileIdent[] = "$Id$";

owl_global g;

int main(int argc, char **argv, char **env)
{
  WINDOW *recwin, *sepwin, *typwin, *msgwin;
  owl_editwin *tw;
  owl_popwin *pw;
  int j, ret, initialsubs, debug, argcsave, followlast;
  int newmsgs, zpendcount, nexttimediff;
  struct sigaction sigact;
  char *configfile, *tty, *perlout, *perlerr, **argvsave, buff[LINE], startupmsg[LINE];
  owl_filter *f;
  owl_style *s;
  time_t nexttime, now;
  struct tm *today;
  char *dir;
#ifdef HAVE_LIBZEPHYR
  ZNotice_t notice;
#endif
#if OWL_STDERR_REDIR
  int newstderr;
#endif

  argcsave=argc;
  argvsave=argv;
  configfile=NULL;
  tty=NULL;
  debug=0;
  initialsubs=1;
  if (argc>0) {
    argv++;
    argc--;
  }
  while (argc>0) {
    if (!strcmp(argv[0], "-n")) {
      initialsubs=0;
      argv++;
      argc--;
    } else if (!strcmp(argv[0], "-c")) {
      if (argc<2) {
        fprintf(stderr, "Too few arguments to -c\n");
        usage();
        exit(1);
      }
      configfile=argv[1];
      argv+=2;
      argc-=2;
    } else if (!strcmp(argv[0], "-t")) {
      if (argc<2) {
        fprintf(stderr, "Too few arguments to -t\n");
        usage();
        exit(1);
      }
      tty=argv[1];
      argv+=2;
      argc-=2;
    } else if (!strcmp(argv[0], "-d")) {
      debug=1;
      argv++;
      argc--;
    } else if (!strcmp(argv[0], "-D")) {
      debug=1;
      unlink(OWL_DEBUG_FILE);
      argv++;
      argc--;
    } else if (!strcmp(argv[0], "-v")) {
      printf("This is owl version %s\n", OWL_VERSION_STRING);
      exit(0);
    } else {
      fprintf(stderr, "Uknown argument\n");
      usage();        
      exit(1);
    }
  }

#ifdef HAVE_LIBZEPHYR
  /* zephyr init */
  ret=owl_zephyr_initialize();
  if (ret) {
    exit(1);
  }
#endif
  
  /* signal handler */
  /*sigact.sa_handler=sig_handler;*/
  sigact.sa_sigaction=sig_handler;
  sigemptyset(&sigact.sa_mask);
  sigact.sa_flags=SA_SIGINFO;
  sigaction(SIGWINCH, &sigact, NULL);
  sigaction(SIGALRM, &sigact, NULL);
  sigaction(SIGPIPE, &sigact, NULL);

  /* screen init */
  if (!getenv("TERMINFO")) {
    sprintf(buff, "TERMINFO=%s", TERMINFO);
    putenv(buff);
    owl_function_debugmsg("startup: setting TERMINFO to %s", TERMINFO);
  } else {
    owl_function_debugmsg("startup: leaving TERMINFO as %s from envrionment", getenv("TERMINFO"));
  }
  initscr();
  start_color();
#ifdef HAVE_USE_DEFAULT_COLORS
  use_default_colors();
#endif
  raw();
  noecho();

  /* define simple color pairs */
  if (has_colors() && COLOR_PAIRS>=8) {
    init_pair(OWL_COLOR_BLACK,   COLOR_BLACK,   -1);
    init_pair(OWL_COLOR_RED,     COLOR_RED,     -1);
    init_pair(OWL_COLOR_GREEN,   COLOR_GREEN,   -1);
    init_pair(OWL_COLOR_YELLOW,  COLOR_YELLOW,  -1);
    init_pair(OWL_COLOR_BLUE,    COLOR_BLUE,    -1);
    init_pair(OWL_COLOR_MAGENTA, COLOR_MAGENTA, -1);
    init_pair(OWL_COLOR_CYAN,    COLOR_CYAN,    -1);
    init_pair(OWL_COLOR_WHITE,   COLOR_WHITE,   -1);
  }

  /* owl global init */
  owl_global_init(&g);
  if (debug) owl_global_set_debug_on(&g);
  owl_function_debugmsg("startup: first available debugging message");
  owl_global_set_startupargs(&g, argcsave, argvsave);
#ifdef HAVE_LIBZEPHYR
  owl_global_set_havezephyr(&g);
#endif
  owl_global_set_haveaim(&g);

#if OWL_STDERR_REDIR
  /* Do this only after we've started curses up... */
  owl_function_debugmsg("startup: doing stderr redirection");
  newstderr = stderr_replace();
#endif   

  /* create the owl directory, in case it does not exist */
  owl_function_debugmsg("startup: creating owl directory, if not present");
  dir=owl_sprintf("%s/%s", owl_global_get_homedir(&g), OWL_CONFIG_DIR);
  mkdir(dir, S_IRWXU);
  owl_free(dir);

  /* set the tty, either from the command line, or by figuring it out */
  owl_function_debugmsg("startup: setting tty name");
  if (tty) {
    owl_global_set_tty(&g, tty);
  } else {
    owl_global_set_tty(&g, owl_util_get_default_tty());
  }

  /* setup the built-in styles */
  owl_function_debugmsg("startup: creating built-in styles");
  s=owl_malloc(sizeof(owl_style));
  owl_style_create_internal(s, "default", &owl_stylefunc_default,
                            "Default message formatting");
  owl_global_add_style(&g, s);

  s=owl_malloc(sizeof(owl_style));
  owl_style_create_internal(s, "basic", &owl_stylefunc_basic,
                            "Basic message formatting.");
  owl_global_add_style(&g, s);
#if 0
  s=owl_malloc(sizeof(owl_style));
  owl_style_create_internal(s, "vt", &owl_stylefunc_vt,
                            "VT message formatting.");
  owl_global_add_style(&g, s);
#endif
  s=owl_malloc(sizeof(owl_style));
  owl_style_create_internal(s, "oneline", &owl_stylefunc_oneline,
                            "Formats for one-line-per-message");
  owl_global_add_style(&g, s);

  /* setup the default filters */
  /* the personal filter will need to change again when AIM chat's are
   *  included.  Also, there should be an %aimme% */
  owl_function_debugmsg("startup: creating default filters");
  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "personal", "( type ^zephyr$ "
                             "and class ^message$ and instance ^personal$ "
                             "and ( recipient ^%me%$ or sender ^%me%$ ) ) "
                             "or ( type ^aim$ and login ^none$ )");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "trash", "class ^mail$ or opcode ^ping$ or type ^admin$ or ( not login ^none$ )");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "ping", "opcode ^ping$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "auto", "opcode ^auto$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "login", "not login ^none$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "reply-lockout", "class ^noc or class ^mail$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "out", "direction ^out$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "aim", "type ^aim$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "zephyr", "type ^zephyr$");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "none", "false");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  f=owl_malloc(sizeof(owl_filter));
  owl_filter_init_fromstring(f, "all", "true");
  owl_list_append_element(owl_global_get_filterlist(&g), f);

  /* set the current view */
  owl_function_debugmsg("startup: setting the current view");
  owl_view_create(owl_global_get_current_view(&g), "main", f, owl_global_get_style_by_name(&g, "default"));

  /* AIM init */
  owl_function_debugmsg("startup: doing AIM initialization");
  owl_aim_init();

  /* process the startup file */
  owl_function_debugmsg("startup: processing startup file");
  owl_function_source(NULL);

  /* read the config file */
  owl_function_debugmsg("startup: processing config file");
  owl_context_set_readconfig(owl_global_get_context(&g));
  perlerr=owl_perlconfig_readconfig(configfile);
  if (perlerr) {
    endwin();
    fprintf(stderr, "\nError parsing configfile: %s\n", perlerr);
    exit(1);
  }

  /* if the config defines a formatting function, add 'perl' as a style */
  if (owl_global_is_config_format(&g)) {
    owl_function_debugmsg("Found perl formatting");
    s=owl_malloc(sizeof(owl_style));
    owl_style_create_perl(s, "perl", "owl::_format_msg_legacy_wrap",
                          "User-defined perl style that calls owl::format_msg"
                          "with legacy global variable support");
    owl_global_add_style(&g, s);
    owl_global_set_default_style(&g, "perl");
  }

  /* execute the startup function in the configfile */
  owl_function_debugmsg("startup: executing perl startup, if applicable");
  perlout = owl_perlconfig_execute("owl::startup();");
  if (perlout) owl_free(perlout);
  
  /* hold on to the window names for convenience */
  msgwin=owl_global_get_curs_msgwin(&g);
  recwin=owl_global_get_curs_recwin(&g);
  sepwin=owl_global_get_curs_sepwin(&g);
  typwin=owl_global_get_curs_typwin(&g);
  tw=owl_global_get_typwin(&g);

  /* welcome message */
  owl_function_debugmsg("startup: creating splash message");
  strcpy(startupmsg, "-----------------------------------------------------------------------\n");
  sprintf(buff,      "Welcome to Owl version %s.  Press 'h' for on-line help. \n", OWL_VERSION_STRING);
  strcat(startupmsg, buff);
  strcat(startupmsg, "                                                                       \n");
  strcat(startupmsg, "If you would like to receive release announcements about Owl you can   \n");
  strcat(startupmsg, "join the owl-users@mit.edu mailing list at http://web.mit.edu/ktools/  \n");
  strcat(startupmsg, "                                                                 ^ ^   \n");
  strcat(startupmsg, "                                                                 OvO   \n");
  strcat(startupmsg, "Please report any bugs or suggestions to bug-owl@mit.edu        (   )  \n");
  strcat(startupmsg, "-----------------------------------------------------------------m-m---\n");
  owl_function_adminmsg("", startupmsg);
  sepbar(NULL);

  wrefresh(sepwin);

  /* load zephyr subs */
  if (initialsubs) {
    owl_function_debugmsg("startup: loading initial zephyr subs");
    /* load normal subscriptions */
    ret=owl_zephyr_loadsubs(NULL);
    if (ret==-1) {
      owl_function_adminmsg("", "Error loading zephyr subscriptions, file inaccessable");
    } else if (ret!=0) {
      owl_function_adminmsg("", "Error loading zephyr subscriptions");
    }
    
    if (ret!=-1) {
      owl_global_add_userclue(&g, OWL_USERCLUE_CLASSES);
    }

    /* load login subscriptions */
    if (owl_global_is_loginsubs(&g)) {
      owl_function_debugmsg("startup: loading login subs");
      owl_function_loadloginsubs(NULL);
    }
  }

  /* First buddy check to sync the list without notifications */
  owl_function_debugmsg("startup: doing initial zephyr buddy check");
  owl_function_zephyr_buddy_check(0);

  /* set the startup and default style, based on userclue and presence of a
   * formatting function */
  owl_function_debugmsg("startup: setting startup and default style");
  if (0 != strcmp(owl_global_get_default_style(&g), "__unspecified__")) {
    /* the style was set by the user: leave it alone */
  } else if (owl_global_is_config_format(&g)) {
    owl_global_set_default_style(&g, "perl");
  } else if (owl_global_is_userclue(&g, OWL_USERCLUE_CLASSES)) {
    owl_global_set_default_style(&g, "default");
  } else {
    owl_global_set_default_style(&g, "basic");
  }

  /* zlog in if we need to */
  if (owl_global_is_startuplogin(&g)) {
    owl_function_debugmsg("startup: doing zlog in");
    owl_zephyr_zlog_in();
  }

  owl_function_debugmsg("startup: set style for the view");
  owl_view_set_style(owl_global_get_current_view(&g), 
                     owl_global_get_style_by_name(&g, owl_global_get_default_style(&g)));   

  owl_function_debugmsg("startup: setting context interactive");
  owl_context_set_interactive(owl_global_get_context(&g));

  nexttimediff=10;
  nexttime=time(NULL);

  owl_function_debugmsg("startup: entering main loop");
  /* main loop */
  while (1) {

    /* if a resize has been scheduled, deal with it */
    owl_global_resize(&g, 0, 0);

    /* these are here in case a resize changes the windows */
    msgwin=owl_global_get_curs_msgwin(&g);
    recwin=owl_global_get_curs_recwin(&g);
    sepwin=owl_global_get_curs_sepwin(&g);
    typwin=owl_global_get_curs_typwin(&g);

    followlast=owl_global_should_followlast(&g);
    
    /* Do AIM stuff */
    if (owl_global_is_doaimevents(&g)) {
      owl_aim_process_events();

      if (owl_global_is_aimloggedin(&g)) {
        if (owl_timer_is_expired(owl_global_get_aim_buddyinfo_timer(&g))) {
          /* owl_buddylist_request_idletimes(owl_global_get_buddylist(&g)); */
          owl_timer_reset(owl_global_get_aim_buddyinfo_timer(&g));
        }
      }
    }

    /* little hack */
    now=time(NULL);
    today=localtime(&now);
    if (today->tm_mon==9 && today->tm_mday==31 && owl_global_get_runtime(&g)<600) {
      if (time(NULL)>nexttime) {
        if (nexttimediff==1) {
          nexttimediff=10;
        } else {
          nexttimediff=1;
        }
        nexttime+=nexttimediff;
        owl_hack_animate();
      }
    }

    /* Grab incoming messages. */
    newmsgs=0;
    zpendcount=0;
    while(owl_zephyr_zpending() || owl_global_messagequeue_pending(&g)) {
#ifdef HAVE_LIBZEPHYR
      struct sockaddr_in from;
#endif
      owl_message *m=NULL;
      owl_filter *f;

      /* grab the new message, stick it in 'm' */
      if (owl_zephyr_zpending()) {
#ifdef HAVE_LIBZEPHYR
        /* grab a zephyr notice, but if we've done 20 without stopping,
           take a break to process keystrokes etc. */
        if (zpendcount>20) break;
        ZReceiveNotice(&notice, &from);
        zpendcount++;
        
        /* is this an ack from a zephyr we sent? */
        if (owl_zephyr_notice_is_ack(&notice)) {
          owl_zephyr_handle_ack(&notice);
          continue;
        }
        
        /* if it's a ping and we're not viewing pings then skip it */
        if (!owl_global_is_rxping(&g) && !strcasecmp(notice.z_opcode, "ping")) {
          continue;
        }

        /* create the new message */
        m=owl_malloc(sizeof(owl_message));
        owl_message_create_from_znotice(m, &notice);
#endif
      } else if (owl_global_messagequeue_pending(&g)) {
        m=owl_global_messageuque_popmsg(&g);
      }
      
      /* if this message it on the puntlist, nuke it and continue */
      if (owl_global_message_is_puntable(&g, m)) {
        owl_message_free(m);
        continue;
      }

      /* otherwise add it to the global list */
      owl_messagelist_append_element(owl_global_get_msglist(&g), m);
      newmsgs=1;

      /* let the config know the new message has been received */
      owl_perlconfig_getmsg(m, 0, NULL);

      /* add it to any necessary views; right now there's only the current view */
      owl_view_consider_message(owl_global_get_current_view(&g), m);

      /* do we need to autoreply? */
      if (owl_global_is_zaway(&g)) {
        if (owl_message_is_type_zephyr(m)) {
          owl_zephyr_zaway(m);
        } else if (owl_message_is_type_aim(m)) {
          /* can't do this, there's no mechanism not to start a loop */
          /* owl_aim_send_im(owl_message_get_sender(m), owl_global_get_zaway_msg(&g)); */
        }
      }

      /* ring the bell if it's a personal */
      if (owl_global_is_personalbell(&g) &&
          !owl_message_is_loginout(m) &&
          !owl_message_is_mail(m) &&
          owl_message_is_private(m)) {
        owl_function_beep();
      }

      /* if it matches the alert filter, do the alert action */
      f=owl_global_get_filter(&g, owl_global_get_alert_filter(&g));
      if (f && owl_filter_message_match(f, m)) {
        owl_function_command(owl_global_get_alert_action(&g));
      }

      /* if it's a zephyr login or logout, update the zbuddylist */
      if (owl_message_is_type_zephyr(m) && owl_message_is_loginout(m)) {
        if (owl_message_is_login(m)) {
          owl_zbuddylist_adduser(owl_global_get_zephyr_buddylist(&g), owl_message_get_sender(m));
        } else if (owl_message_is_logout(m)) {
          owl_zbuddylist_deluser(owl_global_get_zephyr_buddylist(&g), owl_message_get_sender(m));
        } else {
          owl_function_error("Internal error: received login notice that is neither login nor logout");
        }
      }

      /* check for burning ears message */
      /* this is an unsupported feature */
      if (owl_global_is_burningears(&g) && owl_message_is_burningears(m)) {
        char *buff;
        buff = owl_sprintf("@i(Burning ears message on class %s)", owl_message_get_class(m));
        owl_function_adminmsg(buff, "");
        owl_free(buff);
        owl_function_beep();
      }

      /* log the message if we need to */
      if (owl_global_is_logging(&g) || owl_global_is_classlogging(&g)) {
        owl_log_incoming(m);
      }
    }

    /* is it time to check zbuddies? */
    if (owl_global_is_pseudologins(&g)) {
      if (owl_timer_is_expired(owl_global_get_zephyr_buddycheck_timer(&g))) {
        owl_function_debugmsg("Doing zephyr buddy check");
        owl_function_zephyr_buddy_check(1);
        owl_timer_reset(owl_global_get_zephyr_buddycheck_timer(&g));
      }
    }

    /* follow the last message if we're supposed to */
    if (newmsgs && followlast) {
      owl_function_lastmsg_noredisplay();
    }

    /* do the newmsgproc thing */
    if (newmsgs) {
      owl_function_do_newmsgproc();
    }
    
    /* redisplay if necessary */
    /* this should be optimized to not run if the new messages won't be displayed */
    if (newmsgs) {
      owl_mainwin_redisplay(owl_global_get_mainwin(&g));
      sepbar(NULL);
      if (owl_popwin_is_active(owl_global_get_popwin(&g))) {
        owl_popwin_refresh(owl_global_get_popwin(&g));
        /* TODO: this is a broken kludge */
        if (owl_global_get_viewwin(&g)) {
          owl_viewwin_redisplay(owl_global_get_viewwin(&g), 0);
        }
      }
      owl_global_set_needrefresh(&g);
    }

    /* if a popwin just came up, refresh it */
    pw=owl_global_get_popwin(&g);
    if (owl_popwin_is_active(pw) && owl_popwin_needs_first_refresh(pw)) {
      owl_popwin_refresh(pw);
      owl_popwin_no_needs_first_refresh(pw);
      owl_global_set_needrefresh(&g);
      /* TODO: this is a broken kludge */
      if (owl_global_get_viewwin(&g)) {
        owl_viewwin_redisplay(owl_global_get_viewwin(&g), 0);
      }
    }

    /* update the terminal if we need to */
    if (owl_global_is_needrefresh(&g)) {
      /* leave the cursor in the appropriate window */
      if (owl_global_is_typwin_active(&g)) {
        owl_function_set_cursor(typwin);
      } else {
        owl_function_set_cursor(sepwin);
      }
      doupdate();
      owl_global_set_noneedrefresh(&g);
    }

    /* Handle all keypresses.  If no key has been pressed, sleep for a
     * little bit, but otherwise do not.  This lets input be grabbed
     * as quickly as possbile */
    j=wgetch(typwin);
    if (j==ERR) {
      usleep(10);
    } else {
      /* find and activate the current keymap.
       * TODO: this should really get fixed by activating
       * keymaps as we switch between windows... 
       */
      if (pw && owl_popwin_is_active(pw) && owl_global_get_viewwin(&g)) {
        owl_context_set_popless(owl_global_get_context(&g), 
                                owl_global_get_viewwin(&g));
        owl_function_activate_keymap("popless");
      } else if (owl_global_is_typwin_active(&g) 
                 && owl_editwin_get_style(tw)==OWL_EDITWIN_STYLE_ONELINE) {
        /*
          owl_context_set_editline(owl_global_get_context(&g), tw);
          owl_function_activate_keymap("editline");
        */
      } else if (owl_global_is_typwin_active(&g) 
                 && owl_editwin_get_style(tw)==OWL_EDITWIN_STYLE_MULTILINE) {
        owl_context_set_editmulti(owl_global_get_context(&g), tw);
        owl_function_activate_keymap("editmulti");
      } else {
        owl_context_set_recv(owl_global_get_context(&g));
        owl_function_activate_keymap("recv");
      }
      /* now actually handle the keypress */
      ret = owl_keyhandler_process(owl_global_get_keyhandler(&g), j);
      if (ret!=0 && ret!=1) {
        owl_function_makemsg("Unable to handle keypress");
      }
    }

#if OWL_STDERR_REDIR
    stderr_redirect(newstderr);
#endif   

    /* Log any error signals */
    {
      siginfo_t si;
      int signum;
      if ((signum = owl_global_get_errsignal_and_clear(&g, &si)) > 0) {
        owl_function_error("Got unexpected signal: %d %s  (code: %d  fd: %d  band: %d  errno: %d)", 
                           signum, signum==SIGPIPE?"SIGPIPE":"",
                           si.si_code, si.si_fd, si.si_band, si.si_errno);
      }
    }

  }
}

void sig_handler(int sig, siginfo_t *si, void *data)
{
  if (sig==SIGWINCH) {
    /* we can't inturrupt a malloc here, so it just sets a flag
     * schedulding a resize for later
     */
    owl_function_resize();
  } else if (sig==SIGPIPE) {
    /* Set a flag and some info that we got the sigpipe
     * so we can record that we got it and why... */
    owl_global_set_errsignal(&g, sig, si);
  }

}

void usage()
{
  fprintf(stderr, "Owl version %s\n", OWL_VERSION_STRING);
  fprintf(stderr, "Usage: owl [-n] [-d] [-D] [-v] [-h] [-c <configfile>] [-t <ttyname>]\n");
  fprintf(stderr, "  -n      don't load zephyr subscriptions\n");
  fprintf(stderr, "  -d      enable debugging\n");
  fprintf(stderr, "  -D      enable debugging and delete previous debug file\n");
  fprintf(stderr, "  -v      print the Owl version number and exit\n");
  fprintf(stderr, "  -h      print this help message\n");
  fprintf(stderr, "  -c      specify an alternate config file\n");
  fprintf(stderr, "  -t      set the tty name\n");
}

#if OWL_STDERR_REDIR

/* Replaces stderr with a pipe so that we can read from it. 
 * Returns the fd of the pipe from which stderr can be read. */
int stderr_replace(void)
{
  int pipefds[2];
  if (0 != pipe(pipefds)) {
    perror("pipe");
    owl_function_debugmsg("stderr_replace: pipe FAILED\n");
    return -1;
  }
    owl_function_debugmsg("stderr_replace: pipe: %d,%d\n", pipefds[0], pipefds[1]);
  if (-1 == dup2(pipefds[1], 2 /*stderr*/)) {
    owl_function_debugmsg("stderr_replace: dup2 FAILED (%s)\n", strerror(errno));
    perror("dup2");
    return -1;
  }
  return pipefds[0];
}

/* Sends stderr (read from rfd) messages to a file */
void stderr_redirect(int rfd)
{
  int navail, bread;
  char *buf;
  /*owl_function_debugmsg("stderr_redirect: called with rfd=%d\n", rfd);*/
  if (rfd<0) return;
  if (-1 == ioctl(rfd, FIONREAD, (void*)&navail)) {
    return;
  }
  /*owl_function_debugmsg("stderr_redirect: navail = %d\n", navail);*/
  if (navail<=0) return;
  if (navail>256) { navail = 256; }
  buf = owl_malloc(navail+1);
  bread = read(rfd, buf, navail);
  if (buf[navail-1] != '\0') {
    buf[navail] = '\0';
  }
  owl_function_error("Err: %s", buf);
  owl_free(buf);
}

#endif /* OWL_STDERR_REDIR */