ANSI colors no longer render in cmd.exe

[cowwoc]

Please use the following bug reporting template to help produce actionable and reproducible issues. Please try to ensure that the reproduction is minimal so that the team can go through more bugs!

• A brief description
  Color rendering issues #76 and support 256 color #345 added support for ANSI colors. This works in version 10.0.10586 but got broken in version 10.0.14393.

symfony/symfony#19520 confirms that other people are seeing the same problem.

• Expected results
  ANSI colors should render in cmd.exe when applications output to stdout/stderr.
• Actual results (with terminal output if applicable)
  Raw ANSI codes are seen. No colors are rendered.
• Your Windows build number
  10.0.14393
• Steps / All commands required to reproduce the error from a brand new installation
• Run this Java testcase:

public class Test {

    public static void main(String[] args) {
        System.out.println("\033[37;1mwhite\033[0m");
    }
}

1. You will get this output: �[37;1mwhite�[0m
2. Redirect the application stdout to foo.log and run type foo.log
3. Notice that the output now reads white using white text

This is reproducible 100% of the time.

[fpqc]

10.0.14393 is not the most current release. This should work totally fine in 14942 (latest). I think the processing used to be done in bash.exe. It has now been moved directly into conhost.exe as a console mode (enable rendering of terminal escape sequences)

[cowwoc]

@fpqc https://support.microsoft.com/en-ca/help/12387/windows-10-update-history disagrees with your assertion. I tried Windows Update locally (Windows 10 Pro) and it says I have the latest version.

I assume you're talking about an insider release?

Also, did you actually try running my testcase in 14942?

[fpqc]

Yes it's talking about an insider release, and yes I've attempted it.

I'm on 14936. 14942 just came out like an hour ago and I haven't had an opportunity to install it yet.

Anyway, I suspect that the problem with Symfony is that the executable is not set to output to the command prompt in terminal-enabled mode. This is already documented in the posts about 24-bit color, linking to an msdn article iirc.

Link the Symfony people to this article: https://msdn.microsoft.com/en-us/library/windows/desktop/mt638032(v=vs.85).aspx

You need to enable terminal processing mode in the setconsolemode flags.

I know that this documentation applies to the insider builds, not sure if it works in the official ones.

[Manouchehri]

@cowwoc For reporting bugs, you really need to be on the fast ring insider builds. The development here is done way faster than the Windows stable builds can keep up.

[bitcrazed]

Closing:

24-bit color color support was first introduced in Win10 Insiders Update 14931, and isn't available in the Win10 Anniversary Update.

To exercise this feature, you'll need to join the Windows Insiders program and update your PC to install Fast-ring releases. Alternatively, you can opt for slow-ring updates and wait a few weeks for this feature to arrive.

[cowwoc]

Please reopen this issue. I am seeing the same bug in update 14946.

[fpqc]

@cowwoc you have to set the console mode for printf.exe to enable virtual terminal processing, probably by recompiling it. GNUWin32 needs to be recompiled with this console setting enabled for each utility.

It looks like the project is unmaintained. If it matters to you, fork the project, enable this mode as in the documentation (includes two examples), and you should be good to go.

Is there any reason you need gnuwin32? Can't you use the cygwin versions?

Another more recent project is this:

https://github.com/bmatzelle/gow

Last updated 8months ago vs 3 years ago.

[cowwoc]

@fpqc I don't really care about printf. I was just using it because you were doing the same in your testcase. The only thing I care about is getting this to work with Java.

1. I tried the printf version you mentioned and got the same output (no colors).
2. Can you please run my testcase on your end?
3. Why isn't ANSI support enabled by default (without having to enable ENABLE_VIRTUAL_TERMINAL_INPUT?
4. Why were ANSI colors working for me (and others) in past releases and now they no longer do? This seems like a clear regression.
5. How do I find out what console mode a process is running with? I want to reverse-engineer what Java is using.

[fpqc]

@cowwoc No idea, can you set console modes for java.exe? Request that Sun enables it in jvm?

[cowwoc]

@fpqc There is no way to set console modes in Java without using JNI (which is not a realistic option for my use-case). It is also unlikely Sun/Oracle would enable this in the near future.

I think it would help if someone from Microsoft address point 4: why were ANSI colors working in 10.0.10586 but got broken in version 10.0.14393? Something must have changed and I'm not convinced yet this was intentional.

[fpqc]

@cowwoc I dunno. I can't help you, and sorry, but the devs on this Issues page can't help you either. I know Rich Turner (Senior PM on the console enhancement project) has a special work-only Twitter account and maybe you can ask him why the default got changed (vis-a-vis escape sequence processing) and ask if there is a way to turn it on for a console java application.

And if not, report it as a "bug" to Oracle and hope they fix it?

[cowwoc]

@fpqc Perhaps @zadjii-msft could help? He is the one who marked #1173 as fixed.

[fpqc]

@cowwoc I dunno, Mr. Turner is kind of his boss, I think. I think you can turn it on maybe with an environment variable, can't you set those with Java?

Edit: The solution suggested to setconsolemode on Windows for Java is to make a launcher wrapper that just does setconsolemode and then uses java.exe.