Shell script code to determine whether the file exists

#!/bin/sh
# Determine whether the file exists# link：
# date：2013/2/28

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

# The -x parameter here determines whether $myPath exists and has executable permissionsif [ ! -x "$myPath"]; then
 mkdir "$myPath"
fi
# The -d parameter here determines whether $myPath existsif [ ! -d "$myPath"]; then
 mkdir "$myPath"
fi

# Here the -f parameter determines whether $myFile existsif [ ! -f "$myFile" ]; then
 touch "$myFile"
fi
# Other parameters include -n, -n to determine whether a variable has a valueif [ ! -n "$myVar" ]; then
 echo "$myVar is empty"
 exit 0
fi

# determine whether two variables are equalif [ "$var1" = "$var2" ]; then
 echo '$var1 eq $var2'
else
 echo '$var1 not eq $var2'
fi

#shell determines whether the folder exists
#If the folder does not exist, create a folderif [ ! -d "/myfolder" ]; then
 mkdir /myfolder
fi

#shell determines whether the file, directory exists or has permissions
folder="/var/www/"
file="/var/www/log"

# -x parameter determines whether $folder exists and has executable permissionsif [ ! -x "$folder"]; then
 mkdir "$folder"
fi

# -d parameter determines whether $folder existsif [ ! -d "$folder"]; then
 mkdir "$folder"
fi

# -f parameter determines whether $file existsif [ ! -f "$file" ]; then
 touch "$file"
fi

# -n Determine whether a variable has a valueif [ ! -n "$var" ]; then
 echo "$var is empty"
 exit 0
fi

# Determine whether two variables are equalif [ "$var1" = "$var2" ]; then
 echo '$var1 eq $var2'
else
 echo '$var1 not eq $var2'
fi