getpwent bug?

[Dan Nelson]

In the last episode (Jul 21), Jens Rehsack said:
> On 07/16/10 18:13, Dan Nelson wrote:
> 
> Hi Dan,
> 
> > In the last episode (Jul 16), Jens Rehsack said:
> >> On 07/16/10 15:07, Dan Nelson wrote:
> >>> In the last episode (Jul 16), Jens Rehsack said:
> >>>> Could you please take a look to my other mail (getgrent related) - there
> >>>> seems another bug ...
> >>>
> >>> Do you have another one-liner that will reproduce it?  A simple
> >>> "/usr/bin/getent group" doesn't return dupes for me.  Oddly enough, the
> >>> *grent code doesn't use an internal counter, so the bug you found in
> >>> endpwent doesn't exist in endgrent (afaik; the nsswitch code isn't that
> >>> easy to read).
> >>
> >> Not really a one-liner:
> >> perl -MData::Dumper -e 'setgrent; my %dupchk; while( my ( $name,
> >> $grpass, $gid, $members ) = getgrent() ) { print "$name is returned
> >> more than once (No $dupchk{$name} comes here)\n" if( $dupchk{$name}++
> >> ); print Dumper( [ $name, $grpass, $gid, $members ] ) };'
> >>
> >> setgrent() doesn't work here.
> >
> > I ran that and got dupes for group entries that exist both in /etc/groups and
> > my LDAP source, but that's expected.
> 
> You can see here
> http://www.cpantesters.org/cpan/report/f5100ac6-9418-11df-9ebc-c4a68065c34d
> the typical error picture. FreeBSD is the only system, where this error
> occurs.

I don't know how to read perl's test output; what part of that report
failed, and how do you know it was due to getgrent returning duplicate
values?

BTW - I ran your one-liner above on a SLES 10.2 Linux box and a Solaris 10u7
box, and got duplicate entries where groups existed in both /etc/groups and
LDAP, just like on FreeBSD.  I think you may be relying on behaviour that
getgrent doesn't guarantee on any OS.

-- 
	Dan Nelson
	dnelson at allantgroup.com