Input does not register when using Mintty

[amitz]

Hi,

I'm a Windows Ruby developer (we exists :-)) and I'm having problem when using Pry in Mintty terminal. When I try to type input, nothing is being shown on the Pry prompt. When I 'Ctrl C', I can see all the commands I previously tried execute one after the other.

Mintty is used by both Cygwin and MSys2, and I can confirm this problem happens in both. Mintty works fine with Python shell or IRB by the way, so I think it's a Pry issue.

[danowar2k]

Yeah, this happens here, too (using mintty via git for Windows installation).

Also using cygwin terminal on Windows.

[kyrylo]

Does it work in IRB?

[danowar2k]

Okay, I've likely missed to point out important facts. I'm working on Windows 7 and trying to debug Vagrant 2.2.1 code. Working from a minTTY mingw64 terminal I used a Vagrantfile to install the Ruby gems "pry-readline" and "pry".

I then tried binding.pry and the prompt shows, I can type stuff, but nothing happens when I press enter.

Do you mean "Does debugging work in IRB?" or "Does starting pry work in IRB?"

I haven't used IRB from git for Windows mintty yet...

[kyrylo]

The issue description says:

When I try to type input, nothing is being shown on the Pry prompt.

When you use IRB, does it suffer from the same problem?

[danowar2k]

Oh...no, I missed that. Sorry. Typed characters appear on screen. It's only when I type enter that nothing happens. My input is registered and output in the terminal, but it's not really registered in the Ruby program.

The cause seems to be the rb-readline gem, which uses the Win32API:

    @kbhit = Win32API.new("msvcrt", "_kbhit", [], 'I')
[...]
      while (@kbhit.Call == 0)
        # If there is no input, yield the processor for other threads
        sleep(@_keyboard_input_timeout)
      end

kbhit seems to never register the keypresses when using Cygwin or miinTTY, so the rb-readline gem is always in sleep mode.

Seems to be an old problem, see here (from 2012):

http://cygwin.1069669.n5.nabble.com/kbhit-in-a-native-app-run-from-CYGWIN-console-does-not-work-td14287.html

[amit-traiana]

Sorry I can't supply more information. I moved a while ago to a full Linux setup.