格式:
if ....; then
....
elif ....; then
....
else
....
fi
- [ -f "somefile" ] :判断是否是一个文件
- [ -x "/bin/ls" ] :判断/bin/ls是否存在并有可执行权限
- [ -n "$var" ] :判断$var变量是否有值
- [ "$a" = "$b" ] :判断$a和$b是否相等
示例:
#!/bin/bash
if [ ${SHELL} = "/bin/bash" ]; then
echo "your login shell is the bash (bourne again shell)"
else
echo "your login shell is not bash but ${SHELL}"
fi
判断登陆shell脚本是否为bash
while循环 if判断 多进程运行 休眠 日期 综合实例
while true
do
nd=`date "+%H%M"`
if [ "0010" == $nd ] || [ "1507" == $nd ];then
echo "$nd was found"
nohup /usr/local/bin/casperjs /syngooglebudget.js 1 >/cas1.txt 2>&1 &
nohup /usr/local/bin/casperjs /syngooglebudget.js 2 >/cas2.txt 2>&1 &
sleep 3600s
else
sleep 5s
echo "couln'd foun $nd"
fi
done