problem authenticating user with current CVS

[Andrew Tridgell]

> > setresuid() and setresgid() are only introduced in Linux kernels 2.1.44
> > and up.  The autoconf script isn't clever enough to figure out which
> > kernel you're running.  
> 
> Yeah, I read the man page too.  Anyway, don't know much about
> autoconf, but can you type "cat /proc/version" ? ;-)

we don't want to do that. I can easily add a proper autoconf test for
setresuid. I only run 2.1 kernels so I didn't realise it was failing
on earlier kernels.

as an example, this works:

#include <errno.h>

main()
{
        setresuid(1,1,1);
        setresuid(2,2,2);
        if (errno != EPERM) {
                printf("no setresuid\n");
        }
}

I'll make it an autoconf test.