shell bash to determine whether a file or folder exists

 

#shell to determine whether the folder exists

#If the folder does not exist, create the folder
if [ ! -d "/myfolder" ]; then
  mkdir /myfolder
be

#shell determines whether files, directories exist or have permissions


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

# -x parameter to determine whether $folder exists and has executable permissions
if [ ! -x "$folder"]; then
  mkdir "$folder"
be

# -d parameter to determine whether $folder exists
if [ ! -d "$folder"]; then
  mkdir "$folder"
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# -f parameter to determine whether $file exists
if [ ! -f "$file" ]; then
  touch "$file"
be

# -n check if a variable has a value
if [ ! -n "$var" ]; then
  echo "$var is empty"
  exit 0
be

# Check if two variables are equal
if [ "$var1" = "$var2" ]; then
  echo '$var1 eq $var2'
else
  echo '$var1 not eq $var2'
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