Negate if condition in bash script

bash linux if-statement negate

Solution 1:

You can choose:

if [[ $? -ne 0 ]]; then       # -ne: not equal

if ! [[ $? -eq 0 ]]; then     # -eq: equal

if [[ ! $? -eq 0 ]]; then

! inverts the return of the following expression, respectively.

Solution 2:

Better

if ! wget -q --spider --tries=10 --timeout=20 google.com
then
  echo 'Sorry you are Offline'
  exit 1
fi

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