On Thu, Dec 24, 2020 at 11:14:04AM +1000, David O'Brien wrote:
> I don't know if this is expected or not, but it seems very odd:
>
> # lsblk -o=UUID /stratis/labpool/labfs
> lsblk: unknown column: =UUID
>
> [root@serverb ~]# lsblk -o UUID /stratis/labpool/labfs
> UUID
> 0118efb8-66fe-406a-837c-725961bdad4d
>
> [root@serverb ~]# lsblk --output=UUID /stratis/labpool/labfs
> UUID
> 0118efb8-66fe-406a-837c-725961bdad4d
>
>
> From the man(8) page:
> -o, --output list
> Specify which output columns to print. Use --help to get
> a list of all supported columns. The columns may affect
> tree-like output. The default is to use tree for the
> column 'NAME' (see also --tree).
>
> The default list of columns may be extended if list is
> specified in the format +list (e.g., lsblk -o +UUID).
>
> There is no mention of "=" being required, causing failures, etc. I found this quite frustrating.
>
This is common getopt_long() behavior where equal sign is usable only for
long options (and sometimes for optional arguments).
lsblk -o UUID
lsblk --output UUID
lsblk --output=UUID
this is how "=" works in almost all commands and I don't see reason
why we need to be explicit about it for "lsblk -o".
Karel
--
Karel Zak <kzak@xxxxxxxxxx>
http://karelzak.blogspot.com
