Re: pcap_inject() fails with rc 0 on HP-UX

[Guy Harris <guy () alum mit edu>]

Harley Stenzel wrote:

>  However, on HP-UX, that same call returns rc 0.
>
>  I was not able to find a pre-existing bug for this
>  problem, however I was able to find this message:
>  http://www.tcpdump.org/lists/workers/2004/03/msg00103.html
>  indicating that at least in 2004, HP-UX send would not
>  work.

The #ifdeffed-out code was replaced since then.

> 2) It's not clear under what circumstances a rc 0 could ever be
> returned.  Only on retrun from write() or dlrawdatareq() could rc be
> 0.

dlrawdatareq() returns the return value of putmsg(), and putmsg() 
returns 0 on success.

I've checked into the main and x.9 branches a change to, on HP-UX, have 
the inject routine return, on success, the number of bytes it was asked 
to write.  That should at least fix that problem.  (Workaround: use 
pcap_sendpacket(), which is defined to return 0 on success.)

> 3) I ported libnet's transmission code into pcap_inject_dlpi().  It
> still does not work, but the failure mode is different -- it reports
> the number of octets written correctly, but the frame is still not on
> the wire.

I infer from "still not on the wire" that the frame didn't appear on the 
wire with standard libpcap, either.  Is that the case?  If so, my change 
won't fix that - it just changes what's returned to match the 
pcap_inject() API.
-
This is the tcpdump-workers list.
Visit https://lists.sandelman.ca/ to unsubscribe.