linux开机的最后会执行/etc/rc.local，因此可以在此脚本里面添加shell命令自动执行或者自动启动某个进程。
比如
自动输出信息：
#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
echo "hello world!"
exit 0
另一个例子
#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
/usr/local/bin/gen-friendlyelec-release #执行程序
. /etc/friendlyelec-release #执行程序
if [ ! -f /etc/firstuse ]; then #-f作用是判断/etc/firstuse是否为一般文件 !作用是取反
/bin/echo ${BOARD} > /etc/hostname
/bin/sed -i "s/\(127.0.1.1\s*\).*/\1${BOARD}/g" /etc/hosts
/bin/hostname ${BOARD}
/bin/echo "0" > /etc/firstuse
fi
if [ -e /usr/bin/setqtenv ]; then #-e作用是判断/usr/bin/setqtenv是否存在
. /usr/bin/setqtenv
/usr/bin/lcd2usb_print "CPU: {{CPU}}" "Mem: {{MEM}}" "IP: {{IP}}" "LoadAvg: {{LOADAVG}}" 2>&1 > /dev/null&
#/opt/QtE-Demo/run.sh&
fi
exit 0
自动执行另一个shell脚本
#!/bin/sh
sh /etc/init.d/S100auto_wifi_link.sh
echo "wifi finish!!"