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  • shell判断文件,目录是否存在或者具有权限

    shell判断文件,目录是否存在或者具有权限 
    #!/bin/sh 


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


    # 这里的-x 参数判断$myPath是否存在并且是否具有可执行权限 
    if [ ! -x "$myPath"]; then 
    mkdir "$myPath" 
     fi 
     
     # 这里的-d 参数判断$myPath是否存在 
     if [ ! -d "$myPath"]; then 
     mkdir "$myPath" 
     fi 
     
     # 这里的-f参数判断$myFile是否存在 
     if [ ! -f "$myFile" ]; then 
     touch "$myFile" 
     fi 
     
     # 其他参数还有-n,-n是判断一个变量是否是否有值 
     if [ ! -n "$myVar" ]; then 
     echo "$myVar is empty" 
     exit 0 
     fi 
     
     # 两个变量判断是否相等 
     if [ "$var1" = "$var2" ]; then 
     echo '$var1 eq $var2' 
     else 
     echo '$var1 not eq $var2' 
     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/huangmr0811/p/5571062.html
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