概述
众所周知，shell脚本使用的是非交互式方式，在非交互式模式下alias扩展功能默认是关闭的，此时虽然可以定义alias别名，但是shell不会将alias别名扩展成对应的命令，而是将alias别名本身当作命令执行，如果shell内置命令和PATH中均没有与alias别名同名的命令，则shell会找不到指定的命令。
在shell中开启alias
使用shell内置命令shopt命令来开启alias扩展选项。shopt是shell的内置命令，可以控制shell功能选项的开启和关闭，从而控制shell的行为
常用命令：
| Command | Desc |
| shopt -s opt_name | Enable (set) opt_name. |
| shopt -u opt_name | Disable (unset) opt_name. |
| shopt opt_name | Show current status of opt_name. |
比如
查看同义词是否开启（交互模式下）
[/xgj/gj]$shopt expand_aliases expand_aliases on
shopt expand_aliases在交互式模式下 默认是打开的，在非交互式模式下是关闭的,但可以用可shopt来将其开启
shopt -s expand_aliases
实际操作
在我们的项目中某个模块的双机启动脚本（root用户下操作），其中应用的启停使用了alias建立的同义词来操作，如果想要在脚本中使用，必须开启同义词才。
项目启动中会依赖一些环境变量，所以双机启动脚本中需要显式的引入.bash_profile文件。
所以我们将 开启alias的命令放在 .bash_profile中。
source .bash_profile 生效。
脚本如下:
#!/bin/bash ############################################## ## Name: drm_script.ps ## Desc: Duplex switch script of DRM ## Param: None ## Author: Mr Yang ## Date: 2017-07-25 ## Version:V1.0 ## Comment: /drm/.bash_profile must set "shopt -s expand_aliases" so that the alias in the script works well ############################################## #atcive the environment variable source /drm/.bash_profile #main menu of tomcat and jobserver tomcat_jobserver_menu=/drm/drm #main menu of uip and bp1 uip_bp1_menu=/drm/zsmart-uip-8.1.0/bin #stauts of tomcat(webserver) pgrep -f "\-Dz_app=cvbs" status_tomcat=$(pgrep -f Dz_app=cvbs | wc -l) #status of jobserver status_jobserver=$(pgrep -f Dz_app=jobserver | wc -l) #status of uip status_uip=$(pgrep -f Dz_app=uip | wc -l) #status of bp1 status_bp1=$(pgrep -f Dz_app=bp1 | wc -l) #pid of tomcat pid_tomcat=$(pgrep -f Dz_app=cvbs) #pid of jobserver pid_jobserver=$(pgrep -f Dz_app=jobserver) #pid of uip pid_uip=$(pgrep -f Dz_app=uip) #pid of bp1 pid_bp1=$(pgrep -f Dz_app=bp1) ######################################### # #start all processes including tomcat/jobserver/uip/bp1 #start tomcat/jobserver with drmtool #start uip/bp1 with uip.sh # ######################################### startProcess(){ echo "stop first" #there are some problems if you execute startProcess twice or more times,so stop process first stopProcess #start jobserver and tomcat echo "begin to start [tomcat,jobserver]" su - drm -c "cd $tomcat_jobserver_menu; jobstart ; start; exit" > /dev/null 2>&1 echo "sleep 5 seconds..." sleep 5 echo "begin to start [uip,bp1]" #start uip and bp1 su - drm -c "cd $uip_bp1_menu; startuip; startbp1; exit" > /dev/null 2>&1 } ######################################### # #stop all processes including tomcat/jobserver/uip/bp1 #stop tomcat/jobserver with drmtool #stop uip/bp1 with uip.sh # ######################################### stopProcess(){ #stop tomcat、jobserver echo "begin to stop process[tomcat,jobserver]" su - drm -c "cd $tomcat_jobserver_menu ; stop ; jobstop ; exit" > /dev/null 2>&1 echo "process[tomcat,jobserver] stopped sucessfully ,sleep 3 seconds" sleep 3 #stop uip、bp1 echo "begin to stop process[uip,bp1]" su - drm -c "cd $uip_bp1_menu && stopbp1 && stopuip && exit" > /dev/null 2>&1 echo process[uip,bp1] stopped sucessfully } ######################################### # #print the status of each process # ######################################### status(){ #status of tomcat check_status $status_tomcat tomcat #status of jobserver check_status $status_jobserver jobserver #status of uip check_status $status_uip uip #status of bp1 check_status $status_bp1 bp1 } ######################################### # #public function #checking status of each process # ######################################### check_status(){ if [ $1 -eq 1 ] ; then echo "$2 is working..." elif [ $1 -gt 1 ] ;then echo -e " \033[31m more than one $2 process has been start, make sure only one process exists \033[0m " else echo -e " \033[31m $2 stopped \033[0m " fi } ######################################### # #stop all processes by force #find the pid ,and kill the pid # ######################################### forcedstop(){ #kill tomcat kill_process $pid_tomcat cvbs #kill jobserver kill_process $pid_jobserver jobserver #kill uip kill_process $pid_uip uip #kill bp1 kill_process $pid_bp1 bp1 } ######################################### # #public function #kill each process # ######################################### kill_process(){ #check the length of $1 [zero:false, non-zero:true] #two parameters [$1->pid, $2->processName],if $1 is null ,$2 will replace $1 ,$2 turns to $1, so make sure $1 is number if [[ -n $1 && $1 -gt 0 ]] ; then echo "pid: $1 , process: $2" kill -9 $1 if [ $? == 0 ] ; then echo "pid: $1 , process: $2 has been stopped successfully" sleep 1 fi else echo -e " \033[31mpgrep -f Dz_app=$1 without result, $1 has been stopped \033[0m " fi } ######################################### # # $1 variable # $1 can only with (start/stop/status/restart/forcedstop) # ######################################### case "$1" in 'start') startProcess ;; 'stop') stopProcess ;; 'status') status ;; 'restart') #stopProcess #sleep 3 startProcess ;; 'forcedstop') forcedstop ;; *) echo -e "\033[31m Usage: $0 { start | stop | restart | forcedstop | status} \033[0m" exit 1 esac exit 0
