The problem is that || and && only skip one subsequent stanza of a command chain when the condition fails. If you write out a full block structure it makes perfect sense. What you wrote becomes this:
if ! true ; then
echo "This shouldn't print"
else
exit
fi
What you want is this:
if ! true ; then
echo "This shouldn't print"
exit
fi
When you are using Bash's shortcut conditional operators it is better to avoid mixing them. The logic is much easier to understand while you're writing it, and your readers will appreciate your good style.
The main problem is here:
read $input
In bash, usually, $foo
is the value of the variable foo
. Here, you don't want the value, but the name of the variable, so it should be just:
read input
Similarly, in the if
tests, $yes
and $no
should be just yes
and no
, since you just want the strings yes
and no
there.
You could use a case
statement here, which (IMHO) makes it easier to do multiple cases based on input:
case $input in
[Yy]es) # The first character can be Y or y, so both Yes and yes work
echo "Hello!"
echo "Hello!" | festival --tts
;;
[Nn]o) # no or No
echo "Are you sure?"
echo "Are you sure?" | festival --tts
;;
*) # Anything else
echo "Please answer yes or no."
echo "Please answer yes or no." | festival --tts
;;
esac
You could wrap the two echo
statements and the use of festival
in a function to avoid repeating yourself:
textAndSpeech ()
{
echo "$@"
echo "$@" | festival --tts
}
case $input in
[Yy]es) # The first character can be Y or y, so both Yes and yes work
textAndSpeech "Hello!"
;;
[Nn]o) # no or No
textAndSpeech "Are you sure?"
;;
*) # Anything else
textAndSpeech "Please answer yes or no."
;;
esac
With $input
, bash replaces this with its value, which is nothing initially, so the read
command run is:
read
And read
by default stores the input in the variable REPLY
. So you can, if you want, eliminate the input
variable altogether and use $REPLY
instead of $input
.
Also have a look at the select
statement in Bash.
Best Answer
Parsing bash in oneliners is a hard task...
Anyway as a starting point, here goes a suggestion to cover very specific situations like the one presented