[MUD-Dev] Quick socket question

Dr. Cat cat at bga.com
Sat Nov 7 15:06:42 CET 1998

Well, we were going to install Solaris 86 on the Furcadia server machine 
to replace the buggy older version of BSDI it had on it.  But the 
sysadmin out there suggested going to Red Hat Linux instead, because it's 
a BDS family rather than a SYSV family, and there might be fewer 
problems.  I agreed.  I don't know how hard getting it going on SYSV 
would have been, but I know my O'Reilly "Using C on the Unix system" is 
so old that it says Berkeley Unixes have sockets and SYSV don't!  Surely 
SYSV has to have sockets now, what with this "internet" thing having 
gotten so popular since this book was written - don't they?

Anyway, I got a couple compatibility problems involving select() and 
accept() worked out, but I've noticed the return of a problem we 
sometimes had under Linux with the old DragonSpires server, which is the 
ancestor of the Furcadia server code.  After the game is shut down or the 
server code crashes, and it tries to restart, it fails to bind the port 
for the next 15-20 minutes.  This is an improvement over the Linux of 4 
years ago, which apparently didn't have a timeout for this case and would 
leave the game unaccessible for hours, days, or potentially forever until 
I could successfully beg the uncooperative sysadmin of that system for a 
reboot!  Still, I'd like to fix this problem if I can.

I thought at first it was because I wasn't closing the socket when the 
accept() problem I was having crashed it.  But I did a proper operator 
shutdown, which takes the bound socket and does shutdown(mastsock, 2)
and close(mastsock) before existing.  Do I need to do anything more on 
closing to make sure the port is freed up, even if there's some 
recalcitrant user's machine out there still desperately trying to talk to 
it?  Or is there a setsockopt option I need to set differently?  Or is 
there a sysadmin tweak to change that timeout value?  If anyone's dealt 
with this issue under Linux before (or any other Unix that has the same 
issue) I'd appreciate a pointer.  :X)

   Dr. Cat / Dragon's Eye Productions       ||       Free alpha test:
*-------------------------------------------**  http://www.bga.com/furcadia
  Furcadia - a new graphic mud for PCs!     ||  Let your imagination soar!

P.S. I've been to busy to reply to anything on the list, but Raph, I 
really liked the Laws page you set up, and I sent the URL to all of our 
volunteer staff and to some friends to browse through.  Though I would 
have worded that stamp collector thing a lot differently.  I'm still 
waiting for that lunch if you want to talk about how to revise that or 
anything.  :X)

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