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by zokier 2864 days ago
While it is nice that MS is focusing on console and command line now, it seems to me that you are mostly working on improving compatibility with legacy UNIXy stuff.

Do you have some vision or plans to go well beyond the classic UNIXy style of console and command line? I'm thinking in the lines of projects like DomTerm http://domterm.org/ which could have nice interactions with e.g. PowerShell.

2 comments

PM for PowerShell here!

I haven't seen DomTerm before, but it looks pretty awesome. At a glance, it's basically a GUI-fied tmux hosted in Electron? It would be awesome to have in Windows, but wouldn't that just require that DomTerm add support for these ConPty APIs?

In any case, I'm more interested in your proposed interactions. Did you have anything cool in mind? Given that we ship PowerShell on Linux, we could theoretically do some stuff there (including within PowerShell on WSL) before it's hooked up to ConPty

I'm not the person you were asking, but this should interest you.

I've been working on a terminal emulator ( Extraterm http://extraterm.org/ ) with some novel features which would dovetail nicely with how PowerShell works. The first is the ability to send files to the terminal where they can be displayed as text, images, sound, etc or as an opaque download. Extraterm also adds a command `from` which lets you use previous terminal output or files, as input in a command pipeline. See http://extraterm.org/features.html "Reusing Command Output" for a demo. This opens up other, more interactive and iterative workflows. For example, you could show some initial data and then in later commands filter and refine it while visually checking the intermediate results.

What I would like to do sometime is integrate this idea with PowerShell and its approach of processing objects instead of "streams of bytes". It should then be possible to display a PowerShell list of objects directly in the terminal, and then reuse that list in a different command while preserving the "objectness" of the data. For example, you could show a list of user objects in one tab and then in another tab (possibly a different machine) grab that list and filter it the same way as any normal list of objects in PowerShell. You could also directly show tabular data in the terminal, let the user edit it "in place" in the terminal, and then use that editted data in a new command. It allows for more hybrid and interactive workflows in the terminal while still remaining centered around the command line.

Extraterm does these features using extra (custom) vt escape codes. ConPty should allow me to extend these features to Windows too.

Ooooh yeah, that sounds awesome! Going to share this with some people on our team (lots of folks love and use Hyper already, but we're always looking for new stuff to play with).

I would highly recommend you check out the excellent HistoryPx module[1]. Among (many) other things, it supports automatically saving the most recently emitted output to a magic `$__` variable. Theoretically, you could save a lot further back, but you may start to run into memory constraints (turns out .NET objects are a little heavier than text... ;) )

[1]: https://github.com/KirkMunro/HistoryPx

The ConPTY is not just about compatibility with nix. It's about proper remoting of consoles. Unix got that right / Windows got that wrong, and now Windows will finally get it right too -- that it helps nix compat seems like a happy accident (though obviously they want that too, so not so accidental.
Right. For a long time, the MS remoting philosophy was that applications should be remoted, not text streams. The stance goes all the way back to DCOM. That's why PowerShell remoting looks more like a local PowerShell executing commands on a remote machine than it looks like you just connecting to a PowerShell running elsewhere.

The difference is important, since in the traditional MS model, each program that wants to do the remote thing needs to essentially implement its own client-server setup, albeit with a massive amount of help from various runtimes. Named pipes and central authentication made this approach not quite as horrible as it sounds.

This new API is a departure from this model. It will make it possible to just remote via text streams. Perhaps that's uglier --- everyone knows in-band signaling is fragile. But long experience shows they just remoting the damn text streams is easily the more pragmatic option.

I mean, it could be a packet stream where some packets are control packets, and then the Console API could be used and remoted, but you'd need clients that understand it.

The fragility of in-band signaling in the TTY world is not *nix's fault or anything. VMS had that too, since VMS too had to deal with TTYs. The fact is that a) the system evolved from real, hardware TTYs of the 1970s, b) using a text stream with some in-band signaling doesn't even half suck -- mostly it rocks, and all you have to do for it to rock is get the right $TERM value and not output binary files to the tty.

The Windows Console was even more terminally dead. Terminals have their limitations, but honestly, I'll take a terminal, tty/pty, and terminfo, any day over the Windows Console.
You also have to sanitise untrusted data that you want to output.
And remember to use less -R or else pipe to col(1) or whatever.
I want a pipe2(2) flag or an fcntl or something that lets me signal "the other end of this pipe understands ANSI escapes"
It's a difference between making mv/move, cp/copy client-server aware and making the shell running these simple utilities client-server aware.
The Windows way would be to mount the remote filesystem and use local mv and cp. Which works fine, since Windows has excellent remote filesystem support. The Unix world only partially began to catch up to CIFS with the advent of NFSv4 and its lease infrastructure and it still isn't as seamless as the Windows stuff.