Fixed Build 73 TCMD ConPTY tab eat lines after resizing window

[rconn]

Try it with build 77 (already uploaded) and see if it behaves differently.

 

[Alpengreis]

For me: I just run TCMD with a "normal" ConPTY tab, nothing with openconsole).

And have then those effects:

After 2 DIRs in a row and resize TCMD after and other after I resized TCMD first and run immediately a DIR ...

 

[vefatica]

I can't reproduce the bad behavior with build 77.

 

[rconn]

I'm runnind build 76 ... conhost (how would one use openconsole?).

Rename conhost.exe to something else, then copy openconsole.exe to conhost.exe.

 

[vefatica]

Rename conhost.exe to something else, then copy openconsole.exe to conhost.exe.

I tried that quite a while ago, surely before TCMD's conpty's capabilities. I probably didn't consider TCMD at all. I don't recall it doing anything for me. Would it make a significant difference to TCMD/conpty?

 

[rconn]

I tried that quite a while ago, surely before TCMD's conpty's capabilities. I probably didn't consider TCMD at all. I don't recall it doing anything for me. Would it make a significant difference to TCMD/conpty?

Beats me; I've never tried it. I just wanted to know if I needed to try it because that was what you were using.

 

[Alpengreis]

Also here it's still bad with build 77:

I just made a few dirs and then I made window smaller then bigger (maybe also few times) and it looks like the following:

This looks right and it's before I made another smaller and then bigger window:

This looks no more good - you can see the same dir listing again (I made another dir command), which is missing many many lines ... this is after I changed window size to smaller window and bigger again ...

 

[vefatica]

I just tried for 15 min and I couldn't make it screw up as before. I think Norbert's problem might be a different one ... files missing from the middle of a DIR listing! I have not seen that. Could it have something to do with language?

 

[rconn]

This looks no more good - you can see the same dir listing again (I made another dir command), which is missing many many lines ... this is after I changed window size to smaller window and bigger again ...

Are you saying that it works the first (or first few?) times you resize the window, but if you keep resizing it then eventually your DIR listing is bad? That sounds like a different ConPTY bug. (It would not surprise me if you call the ResizePseudoConsole API enough times things will eventually break bad.)

After you manage to break DIR by resizing many times, do subsequent DIR's (or something simpler like MEMORY) also have missing lines in their output? Or do you only get the bad output once (barring future resizes)?

 

[Alpengreis]

It happens too after, at least after following:

I made 2 dirs in a row, THEN I resize it almost to the top and make it bigger again. Anf BOOM, lines are away in second dir.

AND THE NEW TEST WITH MEMORY:

1) I opened TCMD (fresh)
2) I immediately made the MEMORY command
3) I shrinked the window with right corner - vertically almost to the top of TCMD window
4) I made the window bigger again, then it looks like following:

Looks like, I made TWO memory command, but was JUST ONE!!

 

[vefatica]

OK, I can reproduce something I didn't see (or missed) before. This will help. Make a new directory and go there. Then

do i=1 to 25 ( touch /c %@repeat[x,%i].%@format[02,%i] )

and execute DIR twice.

At this point I'd have two DIR listings, the recent one and one above it (for me, scrolled out of sight). They look like this.

Now, without executing any more commands, monkey (several times if necessary) with the vertical size (sorry I can't give exact instructions). Sooner or later you'll see corruption like this (from the more reccent DIR command).

The more monkeying you do, the worse it gets; stuff just gets erased. Things get really bad if you drag the window to less that the apparent 25 row limit.

 

[Alpengreis]

Yup!!! Same effect, I think!!!

 

[rconn]

If you resize the window almost to the top, you will break ConPTY / conhost. And there's nothing I can do about that, other than to say "Why in the world would you do something like that?"

You can report the bug to Microsoft, who will ask you the same thing.

 

[rconn]

The more monkeying you do, the worse it gets; stuff just gets erased. Things get really bad if you drag the window to less that the apparent 25 row limit.

Aaaaaand - how many years have I been telling you not to make windows smaller than 80 x 25?

 

[rconn]

I am closing out this bug, with the note "ConPTY breaks if the user tries hard enough to break ConPTY."

 

[Alpengreis]

Rex, then I think it's ok so now.

Except: the effects would happen also just with small resizing. I will keep an eye on that.

Maybe Vince can also say something about yet.

Thank you very much for the effort!

 

[vefatica]

It happens even if I go nowhere near 25 rows. In a 42 row window, after DIR twice, I wiggled the bottom edge up/down, no more than 3 rows, several times while holding the left button down. The scrollback was hosed.

 

[MGibs]

EDIT: Never mind. I just realized this was under build 76.

I updated to build 77 and all is well.

---

Here's some weird results I received, and I wasn't trying to break ConPTY.

1. Opened TakeCommand with a single TCC tab.
2. Executed a Dir command, which caused the screen to scroll
3. Maximized the TC window (I didn't do any scrolling in the maximized window)
4. Restored the TC Window
5. Executed another Dir command

 

[Alpengreis]

Tried with v36.52.81

What I have is a "gap" after 2nd dir like that (SEE MY STEPS BELOW):

Nothing dramatically it seems ...

What are my steps:

1. Started a new TCMD
2. made dir \windows
3. CLS
4. shrinked the window a bit and made it larger again
5. again dir \windows
6. scrolled up and saw the gap

Maybe even this "effect" is normal because the resizing ... I can live with, no problem ... I posted it just as info ...

 

[Alpengreis]

Hmmmm ... but also FULLSCREEN and back is not good, see here:

My steps are something like that:

1. Started new TCMD
2. dir \windows
3. CLS
4. Fullscreen on
5. Fullscreen off
6. dir \windows

Maybe it needs some combination with cls and fullscreen on/off because it doesnt's always happens it seems ...

Also it seems it has to do with the CLS between ...

So, there is still something not good.

However, without resizing (fullscreen or else) all seems good.

 

[rconn]

You are exercising a conhost / ConPTY bug, not anything in TCMD.

Conhost / ConPTY has no concept of a scrollback buffer; it is strictly viewport sized. When you resize a window smaller, ConPTY will discard the extra lines, not scroll them away to be recalled later.

 

[Alpengreis]

Ooook, Rex, I will stop here with that :-)

Thanks for explaining!