linux基础之echo

echo

   If -e is in effect, the following sequences are recognized:

   \     backslash

   a     alert (BEL)

   b     backspace

   c     produce no further output

   e     escape

   f     form feed

   n     new line

   r     carriage return

   t     horizontal tab

   v     vertical tab

   NNN  byte with octal value NNN (1 to 3 digits)

   xHH   byte with hexadecimal value HH (1 to 2 digits)

echo -e "linuxea.com nwww.linuxea.com"[root@zabbix_agentd ~]# echo -e "linuxea.com nwww.linuxea.com"linuxea.com www.linuxea.com[root@zabbix_agentd ~]#

[root@zabbix_agentd ~]# echo -e "linuxea.com nwww.linuxea.com"linuxea.com www.linuxea.com-t制表符[root@zabbix_agentd ~]# echo -e "linuxea.com twww.linuxea.com"linuxea.com www.linuxea.com垂直制表符-v[root@zabbix_agentd ~]# echo -e "linuxea.com vwww.linuxea.com"linuxea.com

        www.linuxea.com

b删除前一个字符[root@zabbix_agentd ~]# echo -e "linuxea.com bwww.linuxea.com"linuxea.comwww.linuxea.com[root@zabbix_agentd ~]# echo -e "linuxea.com awww.linuxea.com"linuxea.com www.linuxea.com[root@zabbix_agentd ~]# echo -e "linuxea.com www.linuxea.com"

多种颜色[root@zabbix_agentd ~]# echo -e "33[31mwww.linuxea.com33[0m"www.linuxea.com[root@zabbix_agentd ~]#33[31mwww.linuxea.com33[0m 33颜色控制字符开始3表示背景色1m是前景色 ,范围1-7引用颜色的字符 33颜色控制符结束 0m可以用;号隔开在可以这样：echo -e "33[31;1;42;5mwww.linuxea.com33[0m"

-n不自动换行[root@zabbix_agentd ~]# echo -ne "33[31;1;42;5mwww.linuxea.com33[0m"www.linuxea.com[root@zabbix_agentd ~]#

shell中的引用‘’:强引用，变量替换不会进行“”：弱引用，能够执行变量替换``：命令替换，引用命令的执行结echo date +%F-%T