-/* nc: mini-netcat - built from the ground up for LRP
- Copyright (C) 1998 Charles P. Wright
-
- 0.0.1 6K It works.
- 0.0.2 5K Smaller and you can also check the exit condition if you wish.
- 0.0.3 Uses select()
-
- 19980918 Busy Boxed! Dave Cinege
- 19990512 Uses Select. Charles P. Wright
- 19990513 Fixes stdin stupidity and uses buffers. Charles P. Wright
-
- 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 of the License, 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-*/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <signal.h>
-
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <netdb.h>
-#include <sys/time.h>
-#include <sys/ioctl.h>
-#include "busybox.h"
-
-static void timeout(int signum)
+/* nc: mini-netcat - built from the ground up for LRP
+ *
+ * Copyright (C) 1998, 1999 Charles P. Wright
+ * Copyright (C) 1998 Dave Cinege
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+#include "libbb.h"
+
+//config:config NC
+//config: bool "nc"
+//config: default y
+//config: help
+//config: A simple Unix utility which reads and writes data across network
+//config: connections.
+//config:
+//config:config NC_SERVER
+//config: bool "Netcat server options (-l)"
+//config: default y
+//config: depends on NC
+//config: help
+//config: Allow netcat to act as a server.
+//config:
+//config:config NC_EXTRA
+//config: bool "Netcat extensions (-eiw and filename)"
+//config: default y
+//config: depends on NC
+//config: help
+//config: Add -e (support for executing the rest of the command line after
+//config: making or receiving a successful connection), -i (delay interval for
+//config: lines sent), -w (timeout for initial connection).
+//config:
+//config:config NC_110_COMPAT
+//config: bool "Netcat 1.10 compatibility (+2.5k)"
+//config: default n # off specially for Rob
+//config: depends on NC
+//config: help
+//config: This option makes nc closely follow original nc-1.10.
+//config: The code is about 2.5k bigger. It enables
+//config: -s ADDR, -n, -u, -v, -o FILE, -z options, but loses
+//config: busybox-specific extensions: -f FILE and -ll.
+
+#if ENABLE_NC_110_COMPAT
+# include "nc_bloaty.c"
+#else
+
+//usage:#if !ENABLE_NC_110_COMPAT
+//usage:
+//usage:#if ENABLE_NC_SERVER || ENABLE_NC_EXTRA
+//usage:#define NC_OPTIONS_STR "\n"
+//usage:#else
+//usage:#define NC_OPTIONS_STR
+//usage:#endif
+//usage:
+//usage:#define nc_trivial_usage
+//usage: IF_NC_EXTRA("[-iN] [-wN] ")IF_NC_SERVER("[-l] [-p PORT] ")
+//usage: "["IF_NC_EXTRA("-f FILE|")"IPADDR PORT]"IF_NC_EXTRA(" [-e PROG]")
+//usage:#define nc_full_usage "\n\n"
+//usage: "Open a pipe to IP:PORT" IF_NC_EXTRA(" or FILE")
+//usage: NC_OPTIONS_STR
+//usage: IF_NC_EXTRA(
+//usage: "\n -e PROG Run PROG after connect"
+//usage: IF_NC_SERVER(
+//usage: "\n -l Listen mode, for inbound connects"
+//usage: IF_NC_EXTRA(
+//usage: "\n (use -l twice with -e for persistent server)")
+//usage: "\n -p PORT Local port"
+//usage: )
+//usage: "\n -w SEC Timeout for connect"
+//usage: "\n -i SEC Delay interval for lines sent"
+//usage: "\n -f FILE Use file (ala /dev/ttyS0) instead of network"
+//usage: )
+//usage:
+//usage:#define nc_notes_usage ""
+//usage: IF_NC_EXTRA(
+//usage: "To use netcat as a terminal emulator on a serial port:\n\n"
+//usage: "$ stty 115200 -F /dev/ttyS0\n"
+//usage: "$ stty raw -echo -ctlecho && nc -f /dev/ttyS0\n"
+//usage: )
+//usage:
+//usage:#define nc_example_usage
+//usage: "$ nc foobar.somedomain.com 25\n"
+//usage: "220 foobar ESMTP Exim 3.12 #1 Sat, 15 Apr 2000 00:03:02 -0600\n"
+//usage: "help\n"
+//usage: "214-Commands supported:\n"
+//usage: "214- HELO EHLO MAIL RCPT DATA AUTH\n"
+//usage: "214 NOOP QUIT RSET HELP\n"
+//usage: "quit\n"
+//usage: "221 foobar closing connection\n"
+//usage:
+//usage:#endif
+
+/* Lots of small differences in features
+ * when compared to "standard" nc
+ */
+
+static void timeout(int signum UNUSED_PARAM)