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  • shell判断文件是否存在

    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!

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  • 原文地址:https://www.cnblogs.com/ruiy/p/ifExists.html
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