[ros-general] gethostbyaddr() windows behaviour / fixing bad windows behaviour in general

Jan Tisje jan.tisje at gmx.de
Wed Feb 2 14:13:27 CET 2005


I just found the answer to a problem I often had with windows:


Q-10: Why WinDump hangs for some seconds while capturing? How can I 
avoid it?

A: The cause of the slowness is that is that gethostbyaddr(), used by 
Windump to resolve the host names, on Windows actually uses more than 
just DNS and hosts files to translate IP addresses to names: it also 
tries using NetBIOS-over-TCP to do the translation. The translation of 
an IP address to a NetBIOS name requires to send a NetBIOS Name Service 
Node Status Request (see section 4.2.17 of RFC 1002) to the IP address, 
and wait for a reply: the reply will have the machine's NetBIOS name. 
However, if the machine in question isn't running any NetBIOS name 
service code (most non-Windows boxes don't), no reply will come back. An 
ICMP Port Unreachable might get sent out, but that might not cause an 
error to get delivered to the socket on which the request was sent. 
Therefore, the machine trying to get the name might have to wait for the 
request to time out before concluding that it can't get the name for 
that IP address using NetBIOS.  That could take a significant amount of 


I still hope Reactos will fix all those annoying bugs of Windows.

Please allow me to ask if you really did/will fix this problem.

Your answer will significantly increase or decrease my interest in the 
reactos project.  :-)
Because it throws a light on your opinion about dealing with problems 
like this.

Currently I hope reactos will be a nice and small replacement for all 
fat and intransparent MS stuff. (ie remove everything except basic OS)

btw, did anybody read the Bill Gates interview in the Spiegel? Every 
sentence was a lie. He is my most hated person after Bush

and continue good work. World is waiting for ya.


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