When I use break in an if loop in bash it tells me its not valid for bash, what can I use instead?
The use case is, the user is asked a question and if he answers 'no', the script should skip to the next section.
if [[ $ans1_1 = "y" ]]; then
fedoraDeps
elif [[ $ans1_1 = "n" ]]; then
break
else
echo "Answer 'y' or 'n' "
fi
if statements are not "loops", so it doesn't make sense to break out of them. If you want one of your blocks to be a no-op, you can use the built-in : command, which simply does nothing:
if [[ $ans1_1 = y ]]; then
fedoraDeps
elif [[ $ans1_1 = n ]]; then
:
else
echo "Answer 'y' or 'n'"
fi
For this example, I think it makes more sense to use case.
case $ans1_1 in
y)fedoraDeps;;
n);;
*) echo "Answer 'y' or 'n'";;
esac
From man bash:
If the ;; operator is used, no subsequent matches are attempted after the first pattern match.
I agree that case is probably best. But you should probably cast to upper/lower case either way. For the way you had it:
if [[ ${ans1_1,,} = "y" ]]; then
fedoraDeps
elif [[ ${ans1_1,,} = "n" ]]; then
:
else
echo "Answer 'y' or 'n' "
fi
Or, if you wanted uppercase ${ans1_1^^}
This sounds like an ideal case for the select command:
PS3="Please make a selection >"
select foo in 'y' 'n'; do
case $foo in
'Y')
fedoraDeps
;;
'y')
fedoraDeps
;;
'n')
break
;;
esac
done
y/n input, the user will instead have to enter 1 for yes and 2 for no? That seems needlessly complicated for this purpose.
1 or 2 is no more or less complicated than y or n, but if the goal is to keep asking until a valid selection is made, select is one of the best tools for the job.1) y and 2) n, and having to type 1 or 2 rather than y or n, is certainly more complicated just simply typing y/n. I don't see how you can feel otherwise.
break makes only sense in loops... if and case are no loops. use : (does nothing) instead or at case you can resp. should simply remove the break-line.case "${foo,,}" in to prevent having to maintain 2 identical cases.