开发MySQL多实例启动脚本：
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已知mysql多实例启动命令为：mysqld_safe–defaults-file=/data/3306/my.cnf &
停止命令为：mysqladmin -u root -p123456 -S /data/3306/mysql.sock shutdown
要求：用函数，case语句、if语句等实现。
#!/bin/sh
[ -f /etc/init.d/functions ]&&. /etc/init.d/functions||exit
#Define Variables
Port=$1
Mysql_user=root
Mysql_sock=/data/${Port}/mysql.sock
Path=/application/mysql/bin
RETVAL=0
#Define Start Function
start() {
if [ ! -e "$Mysql_sock" ];then
/bin/sh $Path/mysqld_safe --defaults-file=/data/${Port}/my.cnf 2>&1 >/dev/null &
RETVAL=$?
if [ $RETVAL -eq 0 ];then
action "Starting $Port MySQL..." /bin/true
else
action "Starting $Port MySQL..." /bin/false
fi
else
echo "$Port MySQL is Running..."
fi
return $RETVAL
}
#Define Stop Function
stop() {
if [ ! -e "$Mysql_sock" ];then
echo "$Port MySQL is Stopped..."
else
read -p "Please Input $Port MySQL Password:" PWD
Mysql_pwd=$PWD
$Path/mysqladmin -u ${Mysql_user} -p${Mysql_pwd} -S /data/${Port}/mysql.sock shutdown
RETVAL=$?
if [ $RETVAL -eq 0 ];then
action "Stopping $Port MySQL..." /bin/true
else
action "Stopping $Port MySQL..." /bin/false
fi
fi
return $RETVAL
}
case "$2" in
start)
start
RETVAL=$?
;;
stop)
stop
RETVAL=$?
;;
restart)
stop
sleep 3
start
RETVAL=$?
;;
*)
echo -e "USAGE:$0 {3306|3307|3308} {start|stop|restart}"
RETVAL=2
;;
esac
exit $RETVAL
