rlogin -8 uses RAW rather than CBREAK mode

Barry Margolin barmar at think
Fri Dec 21 11:16:43 AEST 1990


I ran into this problem on a Sun, but I notice that the 4.3bsd source has
the same thing.

Normally, rlogin puts the local terminal in CBREAK mode and disables all
the local control characters except the stop and start character (normally
^S and ^Q).  During the session it disables and enables these characters
when it receives TIOC_NOSTOP and TIOC_DOSTOP out-of-band messages from the
remote host.

However, when the "-8" option is supplied, rlogin instead puts the local
terminal in RAW mode, leaves ^S/^Q set as the stop/start characters, and
ignores the TIOC_DOSTOP and TIOC_NOSTOP messages.  This means that the
remote host must implement the stop/start processing.  Why should this be
dependent on 8-bit mode?  The only explanation I can think of is that 8-bit
mode was envisioned to support binary file transfers.  However, the remote
system will still have to disable stop/start, which will still result in
the out-of-band message, so there should be no problem.
--
Barry Margolin, Thinking Machines Corp.

barmar at think.com
{uunet,harvard}!think!barmar



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