Somebody claiming to be Jan Vlach wrote:
> Duh ... for the record:
>
> man stty ...
>
> $ stty -flusho
>
> restores output. Thank you for your attention :-)
And to answer your original question, this is a feature. Or, several
features interacting in a surprising way.
What's happening underneath is the shell putting the terminal in a mode
that ignores ^O when it enters the command line editor, and not giving you
a way to disable output discarding - if you started another long(-ish)
running command and pressed ^O while it was running, you'd get output
back that way as well.
Since I got this far, here's a diff (against 5.8-release) that makes
ksh do the equivalent of 'stty -flusho' before it enters the command
line editor and restore the original state afterward.
With this change, you'll get the command prompt, but the output of
anything you run will disappear until you disable discarding (with 'stty
-flusho' or with ^O while the shell isn't at the prompt). This may or
may not be the least surprising thing to do, but at least you know the
shell is still working.
Index: edit.c
===================================================================
RCS file: /cvs/src/bin/ksh/edit.c,v
retrieving revision 1.40
diff -u -p -r1.40 edit.c
--- edit.c 12 Mar 2015 10:20:30 -0000 1.40
+++ edit.c 6 Nov 2015 19:01:44 -0000
@@ -172,7 +172,7 @@ x_mode(bool onoff)
edchars.eof = cb.c_cc[VEOF];
edchars.werase = cb.c_cc[VWERASE];
cb.c_iflag &= ~(INLCR|ICRNL);
- cb.c_lflag &= ~(ISIG|ICANON|ECHO);
+ cb.c_lflag &= ~(ISIG|ICANON|ECHO|FLUSHO);
/* osf/1 processes lnext when ~icanon */
cb.c_cc[VLNEXT] = _POSIX_VDISABLE;
/* sunos 4.1.x & osf/1 processes discard(flush) when ~icanon */
--
Dave Vandervies
dj3va...@terse.ca / dj3va...@uwaterloo.ca
Plan your future! Make God laugh!
