zoukankan      html  css  js  c++  java
  • linux判断文件是否存在

    #!/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. 
  • 相关阅读:
    扩展欧几里得算法
    Warshall算法
    自己的博客
    使用forever运行web项目
    C#语言基础 Main 函数中的输出输入
    新手第一天学习 C#语言(进制互换)
    Django + Uwsgi + Nginx 实现生产环境部署1
    基于Flask的web微信
    python保存文件UnicodeEncodeError以及reload(sys)后print失效问题
    轮询/长轮询
  • 原文地址:https://www.cnblogs.com/xiongyunqi/p/3735773.html
Copyright © 2011-2022 走看看