Re: [PATCHv2 3/4] nvme: add common APIs for printing tabular format output

[Daniel Wagner <dwagner@suse.de>]

On Tue, Aug 19, 2025 at 02:26:19PM +0530, Nilay Shroff wrote:
> > Sheesh. Can o'worms.
> > 
> > Displaying a table on an ASCII terminal is black magic (check
> > manpage for ncurses ...), and I'm pretty certain that printing
> > spaces for alignment is _not_ the way to go.
> > If you really want to implement this then at the very least use
> > tabs. Ideally check with the ncurses manpage how one can display
> > a table with the correct escape characters.
> > 
> Thanks for the feedback. You're absolutely right that terminal alignment
> can get tricky, and ncurses does provide a more feature-complete way to
> handle interactive table layouts.
> 
> However, for this patch, the intent was much narrower — to make existing
> nvme-cli tabular output (e.g., nvme list, nvme list -v and nvme show-topology)
> more consistent and readable without requiring each command to manually set
> column/row widths. The current implementation just calculates the max width
> per column and pads with spaces, which works for the non-interactive, plain-text
> output we typically expect from CLI tools (including when the output is
> redirected to a file).

I agree with Nilay here. It might not be perfect solution but the
current code is producing non aligned tables (as the examples show).
And another good thing about this patch, it removes the formatting rules
from the printf statements and we only have to touch one place. After
that we could add optional ncurses support if someone fancy this to do.

Thanks,
Daniel