Re: Unhelpful behaviour on Cygwin when "file" isn't installed

[Ralf Wildenhues]

* Olly Betts wrote on Fri, Feb 17, 2006 at 07:55:58PM CET:
> On Tue, Feb 14, 2006 at 08:12:58PM -0600, Bob Friesenhahn wrote:
> > On Tue, 14 Feb 2006, Ralf Wildenhues wrote:
> > >* Olly Betts wrote on Tue, Feb 14, 2006 at 08:06:52PM CET:
> > >>I tried to search for previous references to this issue, but it's pretty 
> > >>much impossible to usefully search for "file"!  Sorry if this is
> > >>rehashing old discussions.
> > >
> > >It's not really, but there is a very similar bug report and patch
> > >outstanding (which I temporarily forgot about):
> > >http://sourceforge.net/mailarchive/forum.php?thread_id=9231830&forum_id=5119
> 
> The message (and problem) are similar, but that's about cross-compiling
> to mingw rather than native building on cygwin it seems.  But a similar
> patch would probably work for cygwin I guess.

Right: the problem is a bit different, the solution hopefully the same
(but a bit more general than outlined there).  I guess we should test
for `file', and evan if we don't have that, still invoke the `nm | egrep' 
part of func_win32_libid on files with names that match what could be an
import library.

> > At one time Cygwin used 'objdump' rather than 'file'.  Later it was 
> > improved to use 'file' since file returns more accurate results.  For 
> > MSYS/MinGW 'objdump' is still used because 'file' does not come with 
> > MSYS.

The issue here is that we
- accept if `file' says import or DLL
- accept if `file' says `archive' but we find import stubs by using
  `objdump .. | egrep'
- ...

We could still make use of the second rule by matching file names if we
don't have `file'.  Just somebody needed to implement it (and test a
lot!).

> The user who reported this to me says that cygwin doesn't come with
> file by default either (he'd installed it very recently, so I guess
> he probably has the latest release).  I'm a little suprised by this,
> but don't have cygwin myself so I can't check if this really is the
> case.

Cygwin is very configurable.  So you can probably choose to (un)install
file, independently of other choices.

Cheers,
Ralf