target the simpler Linux-console ANSI emulation, not xterm
I'd like to suggest that the WSL team focus on a limited but complete terminal emulation on conhost. A natural target is the Linux console emulation.
Like conhost (and unlike xterm), the Linux console terminal emulator grew from the features available on the original IBM PC display hardware, and its capabilities appear to be a more natural fit to conhost's capabilities.
The Linux console is a limited VT102 superset, unlike xterm, which is a large complex emulator. Implementing all of xterm, and getting it all right, will take years and be a continuing source of issues.
Once ptys are working in WSL, developers will very quickly adapt existing Windows terminal emulators (mintty, PuTTY, etc) to WSL (probably via simple TCP/IP forwarding at first), and users that need fully-featured emulation will probably gravitate to these emulators. Also, X11-based terminal emulators become available. Once this happens there will likely be less demand for advanced features on Windows console.
I'd rather see your work go to implementing a limited but complete emulator, and then to other things, rather than a large but incomplete xterm emulation.
We’ve actually added quite a lot of both ANSI, VT-10x and XTerm capabilities to the Windows Console in Windows 10 Anniversary Update and are now able to support, for example, Midnight Commander, Vim, Emacs, Nano, CacaTools, etc.
Please try out the new console in Windows 10 AU Insiders fast-ring builds and file issues on our GitHub issues tracker (https://aka.ms/winbashgithub) if you see anything we’ve missed.