Bug#520744: _SC_GETGR_R_SIZE_MAX returned on amd64 too small
On Thu, Apr 23, 2009 at 11:18:00PM +0200, Aurelien Jarno wrote:
> On Tue, Apr 14, 2009 at 09:32:04AM +0200, Guido Günther wrote:
> > retitle 520744 _SC_GETGR_R_SIZE_MAX returned on amd64 too small
> > user email@example.com
> > usertag 520744 debian-amd64
> > thanks
> > Hi,
> > attached testcase shows that the buffersize for getgrent_r returned via
> > sysconf(_SC_GETGR_R_SIZE_MAX) is too small on amd64. Using the returned
> > 1024 byetes results in ERANGE. i386 and ppc also use 1024 bytes which
> > works fine.
> > While returning -1 is from sysconf is o.k., a too low value certainly is
> > not. Can this be fixed in a Lenny point release since it might break
> > arbitrary software on this architecture?
> What is the example code supposed to do? I have no problem executing it
> $ ./group
> buffer size from sysconf: 1024
> gid: 124
As long as you're not seeing a "Increased buffer to ..." message from
the testcase it's working as expected. When you see the "Increasing
buffer to ..." message the buffer size returned by sysconf is too small
(which is the bug were looking for).
The group that caused the trouble for Andreas had about 70 members (with
a line length in /etc/group of about 515 bytes). No nscd involved.