Go语言视频零基础入门到精通

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  1. shell判断文件,目录是否存在或者具有权限

2. #!/bin/sh

3.

4. myPath="/var/log/httpd/"

5. myFile="/var /log/httpd/access.log"

6.

7. # 这里的-x 参数判断$myPath是否存在并且是否具有可执行权限

8. if [ ! -x "$myPath"]; then

9. mkdir "$myPath"

10. fi

11.

12. # 这里的-d 参数判断$myPath是否存在

13. if [ ! -d "$myPath"]; then

14. mkdir "$myPath"

15. fi

16.

17. # 这里的-f参数判断$myFile是否存在

18. if [ ! -f "$myFile" ]; then

19. touch "$myFile"

20. fi

21.

22. # 其他参数还有-n,-n是判断一个变量是否是否有值

23. if [ ! -n "$myVar" ]; then

24. echo "$myVar is empty"

25. exit 0

26. fi

27.

28. # 两个变量判断是否相等

29. if [ "$var1" = "$var2" ]; then

30. echo "$var1 eq $var2"

31. else

32. echo "$var1 not eq $var2"

33. fi



-f 和-e的区别

Conditional Logic on Files



-a file exists.

-b file exists and is a block special file.

-c file exists and is a character special file.

-d file exists and is a directory.

-e file exists (just the same as -a).

-f file exists and is a regular file.

-g file exists and has its setgid(2) bit set.

-G file exists and has the same group ID as this process.

-k file exists and has its sticky bit set.

-L file exists and is a symbolic link.

-n string length is not zero.

-o Named option is set on.

-O file exists and is owned by the user ID of this process.

-p file exists and is a first in, first out (FIFO) special file or

named pipe.

-r file exists and is readable by the current process.

-s file exists and has a size greater than zero.

-S file exists and is a socket.

-t file descriptor number fildes is open and associated with a

terminal device.

-u file exists and has its setuid(2) bit set.

-w file exists and is writable by the current process.

-x file exists and is executable by the current process.

-z string length is zero.



是用 -s 还是用 -f 这个区别是很大的！