bug#17497: 24.4.50; TTY menu glitches

[Eli Zaretskii]

One more idea: can you try decreasing the number 900 in this snippet
from dispnew.c:

          if (FRAME_TERMCAP_P (f))
            {
              /* Flush out every so many lines.
                 Also flush out if likely to have more than 1k buffered
                 otherwise.   I'm told that some telnet connections get
                 really screwed by more than 1k output at once.  */
              FILE *display_output = FRAME_TTY (f)->output;
              if (display_output)
                {
                  ptrdiff_t outq = __fpending (display_output);
                  if (outq > 900
                      || (outq > 20 && ((i - 1) % preempt_count == 0)))
                    fflush (display_output);
                }
            }

Or maybe even make display_output line-buffered.  I wonder if that has
any effect on the problem.

TIA