socat使用指南：2:工作原理与选项说明

落日映苍穹つ 2023-07-10 08:15 7阅读 0赞

这篇文章继续介绍一下socat的工作原理和选项说明。

# 工作原理 #

socat主要的工作原理如下所示：

初始化

打开连接

数据转发

关闭连接

工作原理说明：在初始化阶段解析命令行和初始化操作，然后顺次打开需要进行数据转发的两个连接，连接打开之后按照需要进行数据的转发，转发完毕关闭连接。

# 命令介绍 #

socat命令执行非常简单，格式如下所示：

> 命令格式：socat \[options\] `<address> <address>`

# options选项 #

<table> 
 <thead> 
  <tr> 
   <th>选项</th> 
   <th>详细说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>-V</td> 
   <td>print version and feature information to stdout, and exit</td> 
  </tr> 
  <tr> 
   <td>-h</td> 
   <td>-?</td> 
  </tr> 
  <tr> 
   <td>-hh</td> 
   <td>like -h, plus a list of all common address option names</td> 
  </tr> 
  <tr> 
   <td>-hhh</td> 
   <td>like -hh, plus a list of all available address option names</td> 
  </tr> 
  <tr> 
   <td>-d[ddd]</td> 
   <td>increase verbosity (use up to 4 times; 2 are recommended)</td> 
  </tr> 
  <tr> 
   <td>-D</td> 
   <td>analyze file descriptors before loop</td> 
  </tr> 
  <tr> 
   <td>-ly[facility]</td> 
   <td>log to syslog, using facility (default is daemon)</td> 
  </tr> 
  <tr> 
   <td>-lf<code>&lt;logfile&gt;</code></td> 
   <td>log to file</td> 
  </tr> 
  <tr> 
   <td>-ls</td> 
   <td>log to stderr (default if no other log)</td> 
  </tr> 
  <tr> 
   <td>-lm[facility]</td> 
   <td>mixed log mode (stderr during initialization, then syslog)</td> 
  </tr> 
  <tr> 
   <td>-lp<code>&lt;progname&gt;</code></td> 
   <td>set the program name used for logging</td> 
  </tr> 
  <tr> 
   <td>-lu</td> 
   <td>use microseconds for logging timestamps</td> 
  </tr> 
  <tr> 
   <td>-lh</td> 
   <td>add hostname to log messages</td> 
  </tr> 
  <tr> 
   <td>-v</td> 
   <td>verbose data traffic, text</td> 
  </tr> 
  <tr> 
   <td>-x</td> 
   <td>verbose data traffic, hexadecimal</td> 
  </tr> 
  <tr> 
   <td>-b<code>&lt;size_t&gt;</code></td> 
   <td>set data buffer size (8192)</td> 
  </tr> 
  <tr> 
   <td>-s</td> 
   <td>sloppy (continue on error)</td> 
  </tr> 
  <tr> 
   <td>-t<code>&lt;timeout&gt;</code></td> 
   <td>wait seconds before closing second channel</td> 
  </tr> 
  <tr> 
   <td>-T<code>&lt;timeout&gt;</code></td> 
   <td>total inactivity timeout in seconds</td> 
  </tr> 
  <tr> 
   <td>-u</td> 
   <td>unidirectional mode (left to right)</td> 
  </tr> 
  <tr> 
   <td>-U</td> 
   <td>unidirectional mode (right to left)</td> 
  </tr> 
  <tr> 
   <td>-g</td> 
   <td>do not check option groups</td> 
  </tr> 
  <tr> 
   <td>-L<code>&lt;lockfile&gt;</code></td> 
   <td>try to obtain lock, or fail</td> 
  </tr> 
  <tr> 
   <td>-W <code>&lt;lockfile&gt;</code></td> 
   <td>try to obtain lock, or wait</td> 
  </tr> 
  <tr> 
   <td>-4</td> 
   <td>prefer IPv4 if version is not explicitly specified</td> 
  </tr> 
  <tr> 
   <td>-6</td> 
   <td>prefer IPv6 if version is not explicitly specified</td> 
  </tr> 
 </tbody> 
</table>

# address说明 #

socat核心功能用于实现socket的转换，在命令行格式中的address所支持的主要类型包括：

*  STDIN STDOUT ：标准输入输出
 *  文件类型：可以指定文件作为数据流参数
 *  TCP类型：支持TCP类型
 *  UDP类型：支持UDP类型
 *  TCP-LISTEN：支持建立TCP监听端口
 *  UDP-LISTEN：支持建立UDP监听端口
 *  EXEC：支持程序的执行