This was a change to getopt() in libc, I noticed it too a little while back.
As far as I can tell on my system, su - works (it did not for a couple days,
till '-' compatibility was put back in getopt)

It was changed because of a standards issue, I can't remember exactly which
standard '-' violates, but I think it was POSIX.

-Sean

On Thu, Jul 11, 2002 at 10:36:33AM -0700, Greywolf wrote:
> Greetings,
> 
> Just upgraded to 1.6-current, and have noted that the "-" option is no
> longer supported; can someone enlighten me as to why this option was
> removed?  It's pretty ubiquitous [it still works under Solaris!], and
> it's been an indication of "full login su" since (time_t)
> (gettimeofday(0) - greywolf.boottime) at least (4.1BSD)...
> 
> If it's a matter of whim, I'd just as soon it were put back.  It's never
> been indicated as a deprecated option.
> 
> 				--*greywolf;
> --
> NetBSD: I Wanna Be Sedated!
> 

-- 
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