#!/bin/sh
# 判斷文件是否存在
# link：www.dbjr.com.cn
# date：2013/2/28

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

# 這里的-x 參數(shù)判斷$myPath是否存在并且是否具有可執(zhí)行權(quán)限
if [ ! -x "$myPath"]; then
 mkdir "$myPath"
fi
# 這里的-d 參數(shù)判斷$myPath是否存在
if [ ! -d "$myPath"]; then
 mkdir "$myPath"
fi

# 這里的-f參數(shù)判斷$myFile是否存在
if [ ! -f "$myFile" ]; then
 touch "$myFile"
fi
# 其他參數(shù)還有-n,-n是判斷一個(gè)變量是否是否有值
if [ ! -n "$myVar" ]; then
 echo "$myVar is empty"
 exit 0
fi

# 兩個(gè)變量判斷是否相等
if [ "$var1" = "$var2" ]; then
 echo '$var1 eq $var2'
else
 echo '$var1 not eq $var2'
fi

實(shí)現(xiàn)代碼二、

#shell判斷文件夾是否存在

#如果文件夾不存在，創(chuàng)建文件夾
if [ ! -d "/myfolder" ]; then
 mkdir /myfolder
fi

#shell判斷文件,目錄是否存在或者具有權(quán)限

folder="/var/www/"
file="/var/www/log"

# -x 參數(shù)判斷 $folder 是否存在并且是否具有可執(zhí)行權(quán)限
if [ ! -x "$folder"]; then
 mkdir "$folder"
fi

# -d 參數(shù)判斷 $folder 是否存在
if [ ! -d "$folder"]; then
 mkdir "$folder"
fi

# -f 參數(shù)判斷 $file 是否存在
if [ ! -f "$file" ]; then
 touch "$file"
fi

# -n 判斷一個(gè)變量是否有值
if [ ! -n "$var" ]; then
 echo "$var is empty"
 exit 0
fi

# 判斷兩個(gè)變量是否相等
if [ "$var1" = "$var2" ]; then
 echo '$var1 eq $var2'
else
 echo '$var1 not eq $var2'
fi

-f 和-e的區(qū)別

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.