Re: How to portably print out Env of a Process

["Arijit Das" <arijit79 at gmail dot com>]

Thanks...

(gdb) p ((char * (*)()) getenv) ("HOME")

seems to be working fine so far. But couldn't make sense of the cast
logically. As you said, ideally, it should have been something like

(gdb) p ((char * (*)(const char *)) getenv) ("HOME")

which doesn't work!

-Arijit

On 5/23/06, Daniel Jacobowitz <drow@false.org> wrote:
> On Tue, May 23, 2006 at 08:56:22AM -0400, Bob Rossi wrote:
> > On Tue, May 23, 2006 at 09:16:42AM +0530, Arijit Das wrote:
> > > Hi,
> > >
> > > Is it possible to print out the env of a process portably with the
> > > same cmdline/script in different os/arch combinations?
> > >
> > > Here is how I tried to do it for i686 - RH3.0:
> > >
> > > (gdb) p (char *) getenv("HOME")
> > > [Switching to Thread 1024 (LWP 17639)]
> > > $1 = 0xdffff781 "/remote/vtghome7/arijit"
> > > (gdb)
> > >
> > > It worked fine.
> > >
> > > But when I tried executing this command in x86_64, I got strange results:
> > >
> > > (gdb) p (char *) getenv("HOME")
> > > [Switching to Thread 182901576896 (LWP 26427)]
> > > $1 = 0xffffffffbfffc790 <Address 0xffffffffbfffc790 out of bounds>
> > > (gdb)
> > >
> > > I guess some kind of 32/64 bits conversion might be messing things up
> > > here....but am not sure exactly what? Any help here?
>
> Exactly.  Try this:
>
> (gdb) p ((char * (*)()) getenv) ("HOME")
>
> I first tried (char * (*) (char *)), but GDB reported that as an
> invalid cast.  I'm not sure why.
>
> >
> > How about, 'shell echo $HOME'?
>
> If you wanted that, "show env", but you don't - the child's might be
> different.
>
> --
> Daniel Jacobowitz
> CodeSourcery