Wrong cursor position when typing ctrl inside speakup-r

[sthibaul]

Copied over from bytefire/speakup#6

When we type ctrl key to stop speech during speakup-r, the cursor ends up a few lines farther from where the speech was when ctrl key was typed. This happens on serial synths, not on softsynth. Also it happens after fix for speakup-r empty line lock up bytefire/speakup#2

[sthibaul]

@grnowak commented:

This seems to be even worse now. Steps to reproduce:
Open a text editor in the text console, and type the following four lines:

This is line 1.
This is line 2.
This is line 3.
This is line 4.

Move the cursor to the top of the file, and issue speakup+r.

When using the soft synth, it reads "this is line 1. This is line 2." and stops. When pressing the ctrl key, and issuing speakup+r again, it reads "this is line 2. This is line 3." and stops again.

With the ltlk synth, it keeps repeating something that sounds like "using idle thread during scheduling." The only way to stop it is to power off the PC. With the bns and dummy synths, speakup+r doesn't work, presumably because neither of those drivers implement indexing.

I have observed this on kernels 5.3.18, 5.4.21, and 5.5. I don't know how far back this issue goes. I only tried it because someone on the speakup list said that speakup+r doesn't work with espeakup.