[mythtv] Closing FDs before exec

[J. Donavan Stanley]

Christopher Pascoe wrote:

>I seem to be quite good at not copying updated diffs from the machines I
>work on to the machine that I send mail from.
>
>I hadn't spotted the ChangeExternalChannel/SpawnApp versions, but I was
>using execl and _exit in my other versions to avoid yet another fork.
>I've reattached an (as yet untested, I'm recording) replacement that
>uses sysconf (like the others do) and replaces LircClient::SpawnApp's
>code with a call to myth_system.  The particular return values in the
>myth_system call are to try to make this mimic system(3)'s behaviour.
>
>It's probably possible to consolidate the ChangeExternalChannel code
>too, and there's another myth_system in libmythui/util.cpp that could
>benefit from similar changes.
>  
>

Committed to CVS.  Thanks!