PATCH: Support "@file"

[Nick Clifton]

Hi Mark,

> The common options section does document "-V" or "-H" because these are
> used inconsistently; some programs use "-V" while others use "-v", and
> similarly for "-h" and "-H".

Yes, that is a shame.  Ideally we ought to give the tools a consistent 
command line interface but it is probably too late to do that here.

 > OK to apply?

Yes, but I think that the section describing the @<file> syntax ought to 
be extended to mention that:

   * The command-line options read from the file are treated as if they 
had been included on the original command line at the point where the 
@<file> was used.

   * The @<file> syntax cannot be used inside the file being parsed.


Also it occurs to me that maybe we ought to have a long-option 
equivalent of @<file>, eg something like:

   --extra-switches-from-file=<file>

This would mean changing libiberty to allow an entry point into the body 
of the expandargv() function or else getting the various different 
projects that use libiberty's expandargv() function to agree on a name 
of the long option.  What do you think ?

Cheers
   Nick