ubuntu 20.04.01与从源代码编译的netcat命令选项的区别

问题描述

默认情况下，在Ubuntu 20.04.01上安装的

netcat命令具有-X选项，但是从源代码编译的netcat 0.7.1没有-X选项。有什么区别？

在Ubuntu 20.04.01上安装的netcat：

foo@foo:~/data/tmp$ netcat --help
netcat: invalid option -- '-'
usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-M ttl]
          [-m minttl] [-O length] [-P proxy_username] [-p source_port]
          [-q seconds] [-s source] [-T keyword] [-V rtable] [-W recvlimit] [-w timeout]
          [-X proxy_protocol] [-x proxy_address[:port]]           [destination] [port]

从源代码编译的netcat 0.7.1：

foo@foo:~/data/tmp$ ./netcat/bin/netcat --help
GNU netcat 0.7.1,a rewrite of the famous networking tool.
Basic usages:
connect to somewhere:  ./netcat/bin/netcat [options] hostname port [port] ...
listen for inbound:    ./netcat/bin/netcat -l -p port [options] [hostname] [port] ...
tunnel to somewhere:   ./netcat/bin/netcat -L hostname:port -p port [options]

Mandatory arguments to long options are mandatory for short options too.
Options:
  -c,--close                close connection on EOF from stdin
  -e,--exec=PROGRAM         program to exec after connect
  -g,--gateway=LIST         source-routing hop point[s],up to 8
  -G,--pointer=NUM          source-routing pointer: 4,8,12,...
  -h,--help                 display this help and exit
  -i,--interval=SECS        delay interval for lines sent,ports scanned
  -l,--listen               listen mode,for inbound connects
  -L,--tunnel=ADDRESS:PORT  forward local port to remote address
  -n,--dont-resolve         numeric-only IP addresses,no DNS
  -o,--output=FILE          output hexdump traffic to FILE (implies -x)
  -p,--local-port=NUM       local port number
  -r,--randomize            randomize local and remote ports
  -s,--source=ADDRESS       local source address (ip or hostname)
  -t,--tcp                  TCP mode (default)
  -T,--telnet               answer using TELNET negotiation
  -u,--udp                  UDP mode
  -v,--verbose              verbose (use twice to be more verbose)
  -V,--version              output version @R_214_4045@ion and exit
  -x,--hexdump              hexdump incoming and outgoing traffic
  -w,--wait=SECS            timeout for connects and final net reads
  -z,--zero                 zero-I/O mode (used for scanning)

Remote port number can also be specified as range.  Example: '1-1024'

解决方法

来自Ubuntu的netcat是Open BSD one：

$ netcat -help
OpenBSD netcat (Debian patchlevel 1.206-1ubuntu1)

然后您编译了GNU版本：

$ ./netcat/bin/netcat --help
GNU netcat 0.7.1,a rewrite of the famous networking tool.

此post讨论了两者之间的区别。

linux linux netcat