Re: [kvm-devel] [Qemu-devel] Re: Storing command line options in images

[Thiemo Seufer <ths@networkno.de>]

Philip Boulain wrote:
> On 13 Aug 2007, at 20:39, Thiemo Seufer wrote:
>> Instead of inventing great and wonderfully complicated schemes, the
>> most sensible way I can think of is to recycle a feature which is now
>> implemented in the GNU toolchain, and apparently stems from Windows:
>>   qemu @qemu.cfg
>
> I'm not familiar with that. Is it just GNU bash shorthand for  qemu `cat 
> qemu.cfg`  ?

I don't think it has anything to do with bash.

Apparently Windows(NT) cmd.exe introduced this as a way to avoid unwieldy
command lines. Cygwin (or MingGW?) added the same to their tools in order
to avoid command line length problems. Not so long ago it was implemented
for gcc and binutils, both as a way to pass overlong argument lists and
to allow for easier scripting.

>>> I wanted an image to be self-contained as much as possible.
>>> That's what I set to achieve.
>> Which tends to collect all the complexity in a single piece.
>> That seems to be the common problem of the option discussed here.
>
> As far as I can tell, this is desirable for easy distribution of images to 
> other machines; this is pretty much my only objection to the 'directory' 
> idea, which is otherwise a nice, clean solution. (If not, I can't really 
> see what's wrong with a one-liner sh script alongside the image, which is 
> basically what has been reinvented.)

It would be a sh script plus a cmd script plus whatever OS X may need
some day, all of them copying the same option line. @file would avoid
that (and allow generic wrapper scripts).


Thiemo