Main functions.

+/* GNU mailutils - a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include "guimb.h"
+#include "getopt.h"
+
+static char short_options[] = "de:f:g:hm:v";
+static struct option long_options[] = {
+  {"debug", no_argument, 0, 'd'},
+  {"expression", required_argument, 0, 'e'},
+  {"file", required_argument, 0, 'f'},
+  {"help", no_argument, 0, 'h'},
+  {"guile-command", required_argument, 0, 'g'},
+  {"version", no_argument, 0, 'v'},
+  {0, 0, 0, 0}
+};
+
+char *program_file;
+char *program_expr;
+int debug_guile;
+
+static void usage (void);
+
+static int g_size;
+static int g_argc;
+static char **g_argv;
+
+#define ARG_INC 16
+
+void
+append_arg (char *arg)
+{
+  if (g_argc == g_size)
+    {
+      g_size += ARG_INC;
+      g_argv = realloc (g_argv, g_size * sizeof (g_argv[0]));
+      if (!g_argv)
+	{
+	  util_error ("not enough memory");
+	  exit (1);
+	}
+    }
+  g_argv[g_argc++] = arg;
+}
+
+int
+main (int argc, char *argv[])
+{
+  int c;
+
+  while ((c = getopt_long (argc, argv, short_options, long_options, NULL))
+	 != -1)
+    switch (c)
+      {
+      case 'd':
+	debug_guile = 1;
+	break;
+      case 'f':
+	program_file = optarg;
+	break;
+      case 'e':
+	program_expr = optarg;
+	break;
+      case 'g':
+	append_arg (optarg);
+	break;
+      case 'h':
+	usage ();
+	exit (0);
+      case 'v':
+	printf ("guimb (" PACKAGE " " VERSION ")\n");
+	exit (0);
+      default:
+	fprintf (stderr,
+		 "Invalid argument. Try guimb --help for more info\n");
+	exit (1);
+      }
+  append_arg (NULL);
+  g_argc--;
+
+  /* Register the desired formats. */
+  {
+    list_t lst;
+    registrar_get_list (&lst);
+    list_append (lst, mbox_record);
+    list_append (lst, path_record);
+    list_append (lst, pop_record);
+    list_append (lst, imap_record);
+    /* Possible supported mailers.  */
+    list_append (lst, sendmail_record);
+    list_append (lst, smtp_record);
+  }
+
+  collect_open_mailbox_file ();
+  if (argv[optind])
+    {
+      for (; argv[optind]; optind++)
+	collect_append_file (argv[optind]);
+    }
+  else
+    collect_append_file ("-");
+  run_main (g_argc, g_argv);
+}
+
+static char usage_str[] =
+  "Usage: guimb [OPTIONS] [MBOX ...]\n"
+  "Process the contents of the specified mailboxes using a Scheme program\n"
+  "or expression.\n"
+  "Options are:\n"
+  "  -d, --debug               Start with debugging evaluator and backtraces.\n"
+  "  -e, --expression EXPR     Execute scheme expression.\n"
+  "  -f, --file PROGFILE       Read program from PROGFILE.\n"
+  "  -g, --guile-command ARG   Append ARG to the command line passed to guile\n"
+  "                            program.\n"
+  "  -h, --help                Display help message.\n"
+  "  -v, --version             Display program version.\n"
+  "\n"
+  "When both --file and --expression are specified, file is evaluated first.\n"
+  "If no mailboxes are specified the standard input is read.\n";
+
+void
+usage ()
+{
+  printf ("%s\n" "Report bugs to <bug-mailutils@gnu.org>\n", usage_str);
+}