Re: [ ! ! hey ] -> [: too many arguments

[Chet Ramey]

On 6/23/22 9:39 AM, Steffen Nurpmeso wrote:
> Hello.
>
> I stumbled over a bug in the MUA i maintain, and when checking
> against what shells do with lonely unary ! i then came to this:
>
>    #?0|kent:tmp$ dash -c 'if [ ! ! hey ]; then echo du; fi'
>    du
>    #?0|kent:tmp$ bash -c 'if [ ! ! hey ]; then echo du; fi'
>    bash: line 1: [: too many arguments
>    #?0|kent:tmp$ busybox.static sh -c 'if [ ! ! hey ]; then echo du; fi'
>    du

Thanks for the report. This appears to have existed for over thirty years,
and you're the first one to report it.

Chet

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/