Missing `]' shell error

Question

while true

do

echo "Enter the number"

read Num

while[$Num -lt 1 || $Num -gt 50]


do

echo "Please enter a new number "

read Num

done

And you need a space in between `while` and `[`. There are tons of shell script examples online. — Peschke, Mar 15 '19 at 03:27
You also need two spaces between `[` and `$Num` and `50` and `]`. — Nasir Riley, Mar 15 '19 at 03:27
As it's written, this would give a "command not found" for `while[`, or the whole `while[...]`, or an error about the glob not matching, so the error message in the title and the code in the script don't even match. — ilkkachu, Mar 15 '19 at 12:10

score 3 · Answer 1 · edited Mar 15 '19 at 12:08

There are some errors and warnings. Also please use shellcheck.net in these kind of situations.

Errors:

Space between while and [.
Space after [ and before ].
Disaster because there is no done, may be you forgot or you just pasted half of your code.
Use [ a ] || [ b ] instead of [ a || b ].

Warnings:

You should use read -r instead of read.
Double quote variable names otherwise this will not work if they have special characters.

Correct Code:

while true
do
    echo "Enter the number"
    read -r Num
    while [ "$Num" -lt 1 ] || [ "$Num" -gt 50 ]
    do
        echo "Please enter a new number "
        read -r Num
    done
done

Missing `]' shell error

1 Answers1