[mythtv] mythfrontend on ubuntu 17.04 testing X11 ICE problems

[Roger James]

On 5 February 2017 3:46:37 pm Peter Bennett <pgbennett at comcast.net> wrote:

> I have just committed new code that greatly improves the experience for
> when the database or backend is down during frontend startup. This is in
> Master, planned for MythTV version 29. There is nothing there as yet to
> address the problem of the database or backend going down after GUI startup.
>
> Peter
>

Just had a quick look at the commit. It looks great.

I still think we need to address issues about front-end startup failing 
without leaving any evidence in the log with default settings. By this I 
mean the "it just wouldn't load and the log just stops with no error 
messages" type of error.

The fault I was originally describing was one of these. It was caused by 
the default error handler in libice just writing some things to stderr and 
calling exit. The use of libice is buried deep in Qt so that problem may 
have to be addressed as a Qt bug. There may be other cases, they are a pain 
to find when the front-end is run in an environment where stderr is lost, 
like that found in most automatic start up mechanisms.  A belt and braces 
approach may be to loop stderr into the log by default.

Another issue is our use of process exit codes that overlap reserved codes 
when the front-end is run from a shell script. For example SIGSEGV being 
misinterpreted as GENERIC_EXIT_INVALID_TIME.

Roger