describing config files

Hi,

I'm a newbie on texinfo, using to write an users manual.
In that process I found the need to detail a configuration file by 
showing a few lines of it, followed by a description of what those lines 
mean, then showing a few more, describing, and so on.

The full config file will go in an appendix (~500 lines long).  But, it 
would be great if the users could have a line number preceding each 
line.  To make that work, the line numbers should be typeset slightly 
smaller or grayed (or even the two), to avoid confusion with the body of 
the config file.

I found no way to do that with texinfo.  I'm almost sure it can't be 
done straight out from the box.  Does anyone has some idea how to do it?

If not possible, and since I think this could be useful in many 
scenarios, it would be great to have something like:

@example
@color{gray}{11} start = 102
@end example

to typeset the 11 in gray (in tt font), a space, and the the start = 102 
in typewriter as usual.

Or perhaps even:

@example
@datafile{11-21}{config.dat}
@end example

To have lines 11 to 21 of config.dat (and only those) inserted there, 
with line numbers in gray, as exemplified above.  Without no line number 
argument it could insert the all file.

Not sure if this is the right place for feature request, but here is it.


João