Re: [Qemu-block] [PATCH v6] qemu-img: add the 'dd' subcommand

[Kevin Wolf]

Am 25.07.2016 um 07:58 hat Reda Sallahi geschrieben:
> This patch adds a basic dd subcommand analogous to dd(1) to qemu-img.
> 
> For the start, this implements the bs, if, of and count options and requires
> both if and of to be specified (no stdin/stdout if not specified) and doesn't
> support tty, pipes, etc.
> 
> The image format must be specified with -O for the output if the raw format
> is not the intended one.
> 
> Two tests are added to test qemu-img dd.
> 
> Signed-off-by: Reda Sallahi <address@hidden>

> +/*
> + * get_size() was needed for the size syntax dd(1) supports which is
> + * different from qemu_strtosz_suffix()
> + *
> + */

(Excess empty line in comment)

Is it really a good idea to stay consistent with dd when this makes the
subcommand inconsistent with all other size specifications in qemu? If I
understand correctly, the only difference is that some suffixes wouldn't
be supported, so you would get an error message rather than surprising
behaviour. I would consider that fine and probably preferrable to adding
another size parser. Nobody uses 'c', 'w' or 'b' anyway.

Kevin