What is the opposite of && in bash?

Question

My bash script is

zenity --question --text=Continue? && echo Continuing...

How can I make it so it would echo Stopping if the user selected no? i.e.:

zenity --question --text=Continue? && echo Continuing... !&& echo Stopping...

score 7 · Accepted Answer · answered Nov 27 '11 at 18:18

7

It's not really the opposite of &&, but something like this might do:

zenity --question --text=Continue? && echo Continuing... || echo Stopping...

answered Nov 27 '11 at 18:18

zigdon

4

Please be cautious! If your "true"-statement isn't a simple `echo` and can return non-zero value, "else"-statement will be executed too! Please try `true && false || echo "Stopping..."` – uzsolt Nov 27 '11 at 19:10

score 3 · Answer 2 · answered Nov 27 '11 at 18:17

3

It's the logical OR, ||:

zenity --question --text=Continue? || echo Continuing...

(So true && cmd, false || cmd and cmd all do the same thing.)

answered Nov 27 '11 at 18:17

Kerrek SB

score 1 · Answer 3 · answered Nov 27 '11 at 18:18

1

Use || to create an "OR list":

zenity --question --text=Continue? && echo Continuing... || echo Stopping...

answered Nov 27 '11 at 18:18

ruakh

score 0 · Answer 4 · answered Nov 27 '11 at 18:19

0

if zenity --question --text='Continue?'
then echo Continuing...
else echo Stopping...
fi

answered Nov 27 '11 at 18:19

zwol

score 0 · Answer 5 · answered Nov 27 '11 at 18:20

0

There may be a way to do it on a single line but I usually use the following which I find a bit more readable:

if zenity --question --text=Continue?
then
        echo Continuing...
else
        echo Stopping...
fi

answered Nov 27 '11 at 18:20

Simon C

5 Answers5