On 4/9/2013 05:09, Mark Morgan Lloyd wrote:
Ludo Brands wrote:
On 04/09/2013 10:14 AM, Mark Morgan Lloyd wrote:
It might be notable that Debian doesn't volunteer a domain name unless
it's able to contact DNS. I'll get onto nslookup, or just use temporary
text (it's only salt for a password hash, and is stored).
One of the problems with uname is that the kernel doesn't have a clue on
how you are connected to the network. Your computer could have 10
network names if it had 10 addresses (not even 10 NIC's required).
Looking up the IP you want the domain name for in a DNS is the only
reliable way. And it is portable.
Thanks Ludo, I'd got there. I think there's still the possibility of ambiguity
if there are multiple DNS servers listed in resolv.conf, but I agree that it's
probably the best way available.
the first DNS server is the one used... if it doesn't respond in X amount of
time, then it may be retried Y times before the next DNS server listed in resolv
is tried... then you loop through the time period and retries again for each
until you get NXDOMAIN or a positive result or have exhausted the list of DNS
servers in resolv... at that point, the app may return an error code about not
being able to reach a DNS server...
in some cases, the non-responding DNS server(s) may be blocked out from further
usage... this may be for some time period or it may require a restart of the
local DNS server app (DNS Proxy on some systems) or reboot of the system... i
have at least one system that acts this way (locking out unresponsive DNS server
entries and requiring a restart of the DNS proxy app)...
my understanding is that this is pretty much all handled by the OS' library code
for performing the lookups...
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
