Breaking loop in shell script - linux

Question

The user inputs sentences for which the number of words has to be counted. If the number is greater than three the sentence should be considered Long. If three or fewer then Short.
I know how to do that, but the rest of the task says make a loop so the user can input sentences until he inputs "n". The problem is I when I input "n" it counts it, but that "n" shouldn't be counted. (It should be a break statement.) How can I break that loop before counting the letter "n"?
#!/bin/bash
recenica=0
while [ $recenica != "n" ]
do
echo Unesite recenicu:
read recenica
if [ $recenica = "n" ]; then # ->>>>> this doesn't work
break
fi
echo $recenica > datoteka
br=$(wc -l datoteka | cut -c1-2)
echo recenica ima $br rijeci
if [ $br -gt 3 ]
then
echo $recenica > Duge.Recenice.IB
elif [ $br -le 3 ]
then
echo $recenica > Kratke.Recenice.IB
else
echo Molimo unijeti nešto
fi
done

Answer 1

You need to use quotes around symbols that expand to more than one word (contain spaces)... this works:
#!/bin/bash
recenica=0
while [ "$recenica" != "n" ] # koristiti dvostruke navodnike ovdje
do
echo Unesite recenicu:
read recenica
if [ "$recenica" = "n" ]; then # koristiti dvostruke navodnike ovdje
break
fi
echo $recenica > datoteka
br=$(wc -l datoteka | cut -c1-2)
echo recenica ima $br rijeci
if [ $br -gt 3 ]
then
echo $recenica > Duge.Recenice.IB
elif [ $br -le 3 ]
then
echo $recenica > Kratke.Recenice.IB
else
echo Molimo unijeti nešto
fi
done

Answer 2

The problem with read is that it will read the entire line and place the contents in recenica. With one word this is fine for the test:
while [ $recenica != "n" ]
However, if you have read more than one word, then the test will fail due to [: too many arguments (as noted by amdn in his answer regarding quoting)
When you enter n you care only about the first word, so limit your test accordingly using parameter expansion/substring extraction:
while [ ${recenica%% *} != "n" ]; do
That allows you to let the while loop control the break logic reducing the entire structure of your code to:
#!/bin/bash
recenica=0
while [ ${recenica%% *} != "n" ]
do
echo Unesite recenicu:
read recenica
echo $recenica > datoteka
br=$(wc -l datoteka | cut -c1-2)
echo recenica ima $br rijeci
if [ $br -gt 3 ]
then
echo $recenica > Duge.Recenice.IB
elif [ $br -le 3 ]
then
echo $recenica > Kratke.Recenice.IB
else
echo Molimo unijeti nešto
fi
done
There are a number of ways to do this, but this approach is fine.