Heim  >  Artikel  >  Backend-Entwicklung  >  Shell-Skriptcode, um festzustellen, ob eine Datei vorhanden ist

Shell-Skriptcode, um festzustellen, ob eine Datei vorhanden ist

高洛峰
高洛峰Original
2017-01-09 13:32:471605Durchsuche

Implementierungscode eins,

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

Implementierungscode zwei,

#shell判断文件夹是否存在
 
#如果文件夹不存在,创建文件夹
if [ ! -d "/myfolder" ]; then
 mkdir /myfolder
fi
 
#shell判断文件,目录是否存在或者具有权限
 
folder="/var/www/"
file="/var/www/log"
 
# -x 参数判断 $folder 是否存在并且是否具有可执行权限
if [ ! -x "$folder"]; then
 mkdir "$folder"
fi
 
# -d 参数判断 $folder 是否存在
if [ ! -d "$folder"]; then
 mkdir "$folder"
fi
 
# -f 参数判断 $file 是否存在
if [ ! -f "$file" ]; then
 touch "$file"
fi
 
# -n 判断一个变量是否有值
if [ ! -n "$var" ]; then
 echo "$var is empty"
 exit 0
fi
 
# 判断两个变量是否相等
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!


Weitere Artikel zum Shell-Skriptcode zur Feststellung, ob eine Datei vorhanden ist, finden Sie auf der chinesischen PHP-Website!


Stellungnahme:
Der Inhalt dieses Artikels wird freiwillig von Internetnutzern beigesteuert und das Urheberrecht liegt beim ursprünglichen Autor. Diese Website übernimmt keine entsprechende rechtliche Verantwortung. Wenn Sie Inhalte finden, bei denen der Verdacht eines Plagiats oder einer Rechtsverletzung besteht, wenden Sie sich bitte an admin@php.cn