• Shell判断文件是否存在


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

      

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  • 原文地址:https://www.cnblogs.com/L-H-R-X-hehe/p/3970891.html
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