Bug#453899: ether_line returns far too much

[Matthew Wilcox <matthew@wil.cx>]

On Sun, Dec 02, 2007 at 10:15:16AM -0500, Clint Adams wrote:
> On Sat, Dec 01, 2007 at 09:49:23PM -0700, Matthew Wilcox wrote:
> >         const char *ethers = mmap(NULL, 100000, PROT_READ, MAP_SHARED, fd, 0);
> > 
> >         ether_line(ethers, &addr, hostname);
> 
> Is there a reason to pass more than one actual line to ether_line()?

Um, I think I just showed an example -- where you want to mmap /etc/ethers
rather than fgets() each line in turn.  Is that a usage that we don't want
to support?  If so, I think the manpage should be amended to state that.

It's somewhat ambiguous, of course:

       The ether_line() function parses a line in /etc/ethers format (ethernet
       address followed by whitespace followed by hostname; '#' introduces  a
       comment)  and  returns  an address and hostname pair, or non-zero if it
       cannot be parsed.  The buffer pointed to by  hostname  must  be  suffi-
       ciently long, for example, have the same length as line.

It doesn't say the line has to be NUL-terminated; my understanding would
be that a \n terminates a line.

-- 
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