On 05/02/2015 01:40, Jon TURNEY wrote:
> On 04/02/2015 23:20, David Stacey wrote:
>> I'm having difficulty running any Qt5 application. These are the
>> commands I'm issuing:
>>
>>      XWin -multiwindow &
>>      export DISPLAY=:0.0
>>      xclock &
>>
>> and I see the clock, so X is up and running. Then:
>>
>>      /usr/lib/qt5/examples/gui/analogclock/analogclock
>>      QXcbConnection: XCB error: 145 (Unknown), sequence: 162, resource
>> id: 0, major c
>>      ode: 140 (Unknown), minor code: 20
>>      Bad system call (core dumped)
>
> Possibly you need to install and start cygserver (See [1])
>
> If so, this is because Qt5 is assuming shared memory is available, which
> could possibly be handled in a better way...
>
> [1]  http://x.cygwin.com/docs/ug/using-shared-memory.html

Yaakov,

This looks like a portability problem in Qt5, where it only handles 
shmget() failing with a return value of -1, not with SIGSYS, to fallback 
to using an image in unshared memory.

Patch attached.

-- 
Jon TURNEY
Volunteer Cygwin/X X Server maintainer