Re: git bisect view's use of DISPLAY environment variable in Cygwin

["Christian Couder" <christian.couder@gmail.com>]

On Tue, Oct 28, 2008 at 6:51 PM, Hannu Koivisto <azure@iki.fi> wrote:
> "Christian Couder" <christian.couder@gmail.com> writes:
>
>> Hi,
>>
>> On Tue, Oct 28, 2008 at 5:28 PM, Hannu Koivisto <azure@iki.fi> wrote:
>>> Greetings,
>>>
>>> git bisect view uses gitk if DISPLAY environment variable is set
>>> and git log otherwise.  Since gitk doesn't require X server in
>>> Cygwin, that seems like a bit questionable condition in that
>>> environment.
>>
>> Do you know any environment variable that we could use to detect we
>> can use gitk in Cygwin?
>
> I looked around and I believe there is no such variable.  I suppose
> the only case where you cannot use gitk is when the user is logged
> on using ssh, telnet, psexec or similar (well, unless you use some
> non-standard Tcl/Tk build which is configured to use X instead of
> Windows graphics).  Then again, I don't think typical Windows
> programs do any checks for such situations.

We need at least a way to detect we are under Cygwin, because we won't
change the current behavior for all platforms.
Is checking for the CYGWIN environment variable enough?

> So, easy fix: always use gitk unless log is specified.  Harder fix:
> figure out a way to test if the login session is such that
> graphical applications can be run.
>
>> You can use "git bisect view log" to use "git log" even if DISPLAY is set.
>
> I'd rather not use undocumented functionality ;)

In this case you can use any "git log" option after "git bisect view"
(for example: git bisect view -p).

Regards,
Christian.