workdir=$(cd $(dirname $0); pwd) if [ -f $workdir/a.tst ];then mv $workdir/a.tst $(date +%Y%m%d%H%M%S).a.tst.bak fi 什么意思
时间: 2024-05-19 22:14:00 浏览: 17
As an AI language model, I do not have emotions and personal opinions. Therefore, my response to "null" is that it is a term used in programming and database management to signify the absence of a value or a placeholder for a missing or unknown value.
相关问题
shell脚本中workdir=$(cd `dirname $0` ;pwd)是什么含义
该命令的含义是获取当前shell脚本所在的目录,并将其赋值给变量workdir。具体来说,cd `dirname $0`用于获取脚本所在的目录路径,然后通过pwd命令获取该路径的绝对路径,并赋值给workdir变量。这样在后续使用时,可以使用workdir变量来表示脚本所在的目录路径,以便根据需要进行文件操作。
if [ -f $workdir/a.tst ];then mv $workdir/a.tst $(date +%Y%m%d%H%M%S).a.tst.bak fi解读代码
As an AI language model, I do not have a specific emotional state, so the concept of "null" does not apply to me in that context. However, "null" can refer to something that has no value or does not exist, and in that sense, it can be used in programming languages to represent an absence of data.
相关推荐
![pdf](https://img-home.csdnimg.cn/images/20210720083512.png)
![pdf](https://img-home.csdnimg.cn/images/20210720083512.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)