case statement only reaching the default case

Aviator

6/25/23, 8:13 AM

echo "Choose one or All"
        read -n1 $sel
        echo "value of $sel
        case $selection in 
        o|O) echo "inside O";;
        a|A) echo "inside A";;
        *) echo "this is default"
        ;;
        esac;

However, it always print value of $sel is default. The case statement is always reaching the default value and it is not reaching other cases. What might be the issue?

0 + 0

command-line

steeldriver

6/25/23, 8:30 AM

You need to be consistent about whether the variable is `$sel` or `$selection` and also it should be `read -n1 sel` (no `$`). You also have an unmatched `"` which I assume is a copy error.

pLumo

6/25/23, 9:15 AM

You might want to check out `select` statement. e.g. `select sel in one all; do break; done; echo $sel;`

Aviator

6/25/23, 1:41 PM

@steeldriver fixed all these things now, still no luck.

Aviator

6/25/23, 1:42 PM

@plumo this returns empty string

steeldriver

6/25/23, 2:30 PM

@Aviator you may [edit] your question to correct the code. It's really impossible to debug code we can't see.

waltinator

6/25/23, 4:35 PM

Always paste your script into `https://shellcheck.net`, a syntax checker, or install `shellcheck` locally. Make using `shellcheck` part of your development process.

pLumo

6/25/23, 10:37 PM

@Aviator , you give the number, not the text. So enter "1" or "2" , then enter. And `$sel` will be the `one` or `all`.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: case statement only reaching the default case

TH: คำสั่ง case ถึง case เริ่มต้นเท่านั้น

RO: declarația casei ajunge doar la cazul implicit

RU: оператор case достигает только случая по умолчанию

VI: tuyên bố trường hợp chỉ đạt đến trường hợp mặc định

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