On Fri, 30 Apr 2021 08:25:12 -0600 Kevin Locke wrote: > Hi All, > > I'm investigating an issue in Git for Windows[^1], which also affects > Cygwin. The issue is that, when using CMD (i.e. Command Prompt) on > Windows 10 1703 or above with "Legacy Console Mode"[^2] disabled, if > TERM=cygwin is set in the environment, the console is not cleared when > vi exits. To demonstrate, with Cygwin 3.2.0, in CMD with "Legacy > Console Mode" disabled: > > cd C:\cygwin64 > set TERM=cygwin > bin\vi etc\bash.bashrc > :q > > After exiting vi, the console window has not been cleared and content > from etc\bash.bashrc remains visible, making further use of the console > difficult until cleared. > > The difference appears to result from enabling > SetConsoleMode(ENABLE_VIRTUAL_TERMINAL_PROCESSING) and > SetConsoleMode(ENABLE_VIRTUAL_TERMINAL_INPUT)[^3] to behave like > xterm-256color when supported[^4] (they are not supported in "Legacy > Console Mode"). > > I'm not too familiar with TTY/PTY handling, much less Cygwin on top of > CMD. It's not clear to me if the alternate screen buffer behaves > differently in CMD than xterm, whether Cygwin has any responsibility, or > if the issue is in how CMD handles ANSI escape sequences. Johannes > Schindelin suggested it may make sense not to enable virtual terminal > processing when TERM=cygwin is set.[^5] Thoughts? > > Any advice or assistance for how to address this issue would be > appreciated. > > Thanks, > Kevin > > [^1]: https://github.com/git-for-windows/git/issues/3177 > [^2]: https://docs.microsoft.com/windows/console/legacymode > [^3]: > https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/cygwin/fhandler_console.cc;h=ebe89fc9f8fd9fcb8102ee9884b8b91f04e88fb1;hb=5eb232ede72e394e280d1a23131267c7002d2c52#l464 > [^4]: > https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/cygwin/fhandler_console.cc;h=ebe89fc9f8fd9fcb8102ee9884b8b91f04e88fb1;hb=5eb232ede72e394e280d1a23131267c7002d2c52#l1327 > [^5]: > https://github.com/git-for-windows/git/issues/3177#issuecomment-828494565
Why on earth do you want to set TERM=cygwin? If you don't set TERM=cygwin, TERM is automatically set to xterm-256color, in which the issue does not occur. -- Takashi Yano <takashi.y...@nifty.ne.jp> -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
