Windows terminal issues caused by winpty

[Tyriar]

This is a meta issue to act as a central place for all winpty issues.

Legend

Icon	Meaning
✔️	Workaround in place
✖️	Still an issue

General

• ✖️ Native Exception in winpty #29540 Random native exceptions
• ✖️ VSCode Terminal drops output from AWS CLI #42847 Output being dropped for some programs (not confirmed)
• ✖️ Duplicate text when resizing integrated terminal #26375 Resizing the terminal will duplicate lines (and generally corrupt the current viewport)
• ✖️ Integrated Terminal glitched output with docker push #47088 Lines are duplicated when viewport is narrow
• ✖️ Git Bash/winpty - blank lines when wrapping in interactive cli #45682 ghci in integrated Terminal doesn't go to newline on reaching line width limit #19785 Various issues with sub-shells like ghci/python
• ✖️ Ansi escape sequences are broken in Terminal. #45516 Running ssh doesn't properly interpret escape sequences
• ✖️ Windows terminal issues caused by winpty #45693 Characters get stuck in viewport in wrong spot in PowerShell
• ✖️ Windows terminal issues caused by winpty #45693 2 spaces are added when space is pressed when launched with the cmder init script

Foreground/background color

• ✖️ VSCode Integrated terminal text color goes crazy after npm or gulp commands #40327 Text color goes crazy when running certain commands
• ✖️ Continuing issue with heroku login with invisible text #41195 Invisible text in some programs
• ✖️ React native, QR Code not showing on terminal #32648 QR codes in terminal printed with background color don't show
• ✖️ PowerShell Interactive Console Keeps Defaulting to White Text #46397 Enable PSReadline support in the integrated console (syntax highlighting, keyboard navigation) PowerShell/vscode-powershell#535 PowerShell colors don't work as expected (I suspect winpty is to blame for this)
• ✖️ Zsh theme is not displayed right in integrated terminal on Windows #47073 Powerlines doesn't display correctly

Process killing / ctrl+c

• ✖️ Ctrl-C doesn't terminate process or clear the line node-pty#7 Ctrl+C doesn't do anything, is unreliable or breaks the viewport
• ✖️ Ctrl+C triggers "Terminate batch job (Y/N)" on Windows which seems to always terminate the job node-pty#168 Ctrl+C presents "Terminate batch job (Y/N)" but it looks like it kills the process regardless
• ✖️ Terminal leaks processes #26807 The process tree is not killed properly when winpty is killed, the current fix which doesn't seem to work for all cases is to get the console process tree and forcefully kill it
• ✖️ Terminal should remember the history of commands after VS Code's restart on Windows #43557 Due to the way we kill the process tree this is preventing the shells from shutting down gracefully and retaining their history

Clearing

• ✖️ Launching Vscode from git bash makes it impossible to clear the terminal window #33730 Clearing the terminal doesn't work in git bash
• ✖️ Running clear in terminal removes viewport content from buffer instead of hiding it xtermjs/xterm.js#106 winpty does not trigger a clear scrollback when cls is run

Tasks

• ✔️ Wrapped lines lead to wrong problems #32042 Line are pre-wrapped by winpty so we are forced to guess where lines are wrapped
• ✔️ Terminal sends the same lines twice #44192 Clearing the screen can redraw lines multiple times

Windows regressions

These issues slipped into stable Windows and took month(s) to get a fix to users as a result.

• ✔️ Terminal: broken text layout #19665 Broken text layout
• ✔️ Python throws IOError in some scripts in Windows Integrated Terminal #36630 IOError in Python

[monk-time]

Shouldn't #45682 be also added to this list?

[Tyriar]

@monk-time added it to the list

[jarbus]

Not sure if this is of any help, but when opening the bash terminal it additionally scrolls all the way down after highlighting the entire terminal. Killing it and opening a new terminal just goes back to the regular highlighting issue. The following image is right after opening a terminal just after opening VSCode

This is additionally on a machine that got a fresh installation of windows an hour prior.

[Astrantia]

@Tyriar It didn't make into 1.29. Are you planning to release the improvements in 1.30?

@ghiscoding this year, I'll be working on this again next month so it will hopefully make it into 1.29.

[cedric05]

with latest fall creators update, windows is psesdo console apis. is vscode planning to use them?
Reference: https://docs.microsoft.com/en-us/windows/console/creating-a-pseudoconsole-session
@Tyriar
i want to give it a try

[ExE-Boss]

@cedric05 This is being done in microsoft/node-pty#236 (see microsoft/node-pty#216 for details).

[namvt13]

I was redirected here by another user, but the issue at #26375 & #47088 has also happened outside of vscode (In my case, it is the terminal of Ubuntu), so it likely to be some OS bug.

[Tyriar]

Adoption of conpty is on the way as @ExE-Boss pointed out, it's currently blocked on VS Code adopting Electron 3 #52629

[Astrantia]

@Tyriar is this shipped in exploration builds if electron 3 is the blocker?

[SetTrend]

cls still doesn't clear scroll buffer on Windows systems. Rather annoying. Particularly when you need to search through long logs.

https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/cls
https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/functions/clear-host

[Tyriar]

ConPTY support is landing in the next Insiders build, this uses a new backend for the terminal on WIndows 10 build number 17692+, this is expected to fix many bugs in the terminal on Windows as we're adopting Microsoft's official pty API. For earlier versions winpty will still be used a many bugs will still remain (unless they're fixed in that project).

If you find any issues with conpty please report them to https://github.com/Microsoft/console (the team who own ConPTY) or this repo (if you think it's an integration issue). You can opt out of conpty by adding this setting:

"terminal.integrated.windowsEnableConpty": false

[Tyriar]

Update: Windows build number 18309+ is now required for ConPTY to be turned on as it was not stable on 17692.