karl_kleinpaste@cis.ohio-state.edu (07/10/90)
Environment: OSx 4.4c; 9825, 98x, 98xe. I've had a problem with rlogin ever since I started using SLIP. My 9825 is configured to do SLIP connections to a variety of machines which dial up and use a bit of code I got via csg from NASA Ames called slipsh to initialize SLIP operation. It also happens when using a hardwired SLIP line between any two of my Pyrs, with dstaddr/ifconfig/route used exactly as in the NSP manual. The problem is that having large amounts of output results in some of that output being lost with quite some frequency. For example, if I "cat .login," as much as half the file doesn't actually appear (my .login is about 2.5Kb), and the next prompt is lost as well. This only occurs when using a modified csh ("cshe") which does command line editing much like tcsh. (In fact, cshe and tcsh share a good bit of extension code.) While reading command input, the tty is in CBREAK mode, and then goes back to canonical mode when cshe is not reading a command. If I disable the command line editor, the problem goes away. The tty always stays in canonical mode, and no data is lost. This doesn't happen when operating on our campus network (reasonably complex ethernet subnets hung off a Proteon ProNet-80 ring), or, for that matter, over any long distance network -- working from the Anaheim Usenix terminal room via rlogin was no problem. It only occurs when using SLIP. Dialed SLIP is occurring at 9600bps using V.32 modems; the machine at the other end, in my case, is a Sun4/110 running 4.0.3c. The Pyr-Pyr ("peer-to-peer?" :-) SLIP link is a null modem cable, at either 19.2K or 9600. I have a (very dim, hence questionable) memory of there having been a bug in the 4.2BSD rlogin code caused by OOB data being used to indicate tty mode changes of this type to the remote end -- something about the tty mode being changed with TIOCSETP, thereby causing an output flush, rather than using TIOCSETN to wait for drain first. Is this possibly the problem I'm up against? How recent is the rlogin incantation in 4.4c? --karl