Bash Shell: Take Control of PS1, PS2, PS3, PS4 and PROMPT_COMMAND

diy534

于 2012-03-22 19:37:25 发布

阅读量754

点赞数

分类专栏： linux 技巧文章标签： command shell ps3 bash string each

linux 技巧专栏收录该内容

5 篇文章

订阅专栏

本文介绍了如何通过修改PS1、PS2、PS3和PS4变量来定制Bash Shell中的提示符字符串。PS1用于设置主提示符，PS2用于设置子shell提示符，默认为'>', PS3用于ksh中select命令的菜单提示符，而PS4则用于调试脚本时的命令前缀。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

PS1 - to set the prompt string, ofcourse!
PS2 - to set the subshell prompt string, which by default is ">", when we enter a command half and press enter, we get the subshell prompt string which is >, then we can complete the command and press enter, it runs. We can change the > to something by modifying this var
PS3 - mostly used in ksh, this is used to define the prompt string displayed by 'select' command, which creates a menu, so in the menu, the prompt string for each option can be defined by changing this one
PS4- we can debug a shell script by putting a set -x while running it, this enables to print each command and then its results a + sign is put before each command, this "+" prompt string can be changed by defining the PS4 var.

http://www.thegeekstuff.com/2008/09/bash-shell-take-control-of-ps1-ps2-ps3-ps4-and-prompt_command/

http://pangaoyuan.iteye.com/blog/1154788