bash-hackers-wiki/docs/syntax/ccmd/user_select.md

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# User selections
## Synopsis
select <NAME>; do
<LIST>
done
select <NAME> in <WORDS>; do
<LIST>
done
# alternative, historical and undocumented syntax
select <NAME>
{
<LIST>
}
select <NAME> in <WORDS>
{
<LIST>
}
## Description
This compound command provides a kind of menu. The user is prompted with
a *numbered list* of the given words, and is asked to input the index
number of the word. If a word was selected, the variable `<NAME>` is set
to this word, and the [list](../../syntax/basicgrammar.md#lists) `<LIST>` is
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executed.
If no `in <WORDS>` is given, then the positional parameters are taken as
words (as if `in "$@"` was written).
Regardless of the functionality, the *number* the user entered is saved
in the variable `REPLY`.
Bash knows an alternative syntax for the `select` command, enclosing the
loop body in `{...}` instead of `do ... done`:
select x in 1 2 3
{
echo $x
}
This syntax is **not documented** and should not be used. I found the
parser definitions for it in 1.x code, and in modern 4.x code. My guess
is that it\'s there for compatiblity reasons. This syntax is not
specified by POSIX(R).
## Examples
``` bash
# select <NAME> in <WORDS>; do
# <LIST>
# done
# meaning e.g.:
clear
echo
echo hit number key 1 2 or 3 then ENTER-key
echo ENTER alone is an empty choice and will loop endlessly until Ctrl-C or Ctrl-D
echo
select OPTIONX in beer whiskey wine liquor ; do
echo you ordered a $OPTIONX
break # break avoids endless loop -- second line to be executed always
done
# place some if else fi business here
# and explain how it makes sense that $OPTIONX is red but OPTIONX is black
# even though both are variables
```
## Portability considerations
## See also