Linux shell 实用脚本

1. 递归修改文件后缀名

find ./ -name "*.c" | awk -F "." '{print $2}' | xargs -i -t mv ./{}.c  ./{}.cpp

2. 判断进程是否已启动

ps -ef | grep 进程名 | grep -v grep
if [ $? -ne 0 ];then
	echo "not runing"
else
	echo "runing"
fi

3. 文件拷贝显示进度

rsync -avh --progress source_file destination_directory/

4. 当前时间后退20s

date;date -s "$(date --date='-20 seconds' '+%Y-%m-%d %H:%M:%S')";date