Document CFE_ES_WriteToSysLog() can be used when CFE_ES_RegisterApp() fails

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On Thu, Apr 26, 2018 at 5:11 PM, Fleming, Thadeus thadeus.fleming@odysseysr.com wrote:
It's clear that CFE_ES_RegisterApp is supposed to be the first CFE
function an app calls, and that the app shouldn't continue if the call
fails.

However, it's not clear whether it's kosher to call
CFE_ES_WriteToSysLog to log failure of CFE_ES_RegisterApp. It appears
to be both safe (the function source doesn't look at the app's entry
in the AppTable) and common practice (e.g. the gen_app_code app
template does it).

I'd suggest that apps be allowed to call WriteToSysLog when
RegisterApp fails, and that the practice is documented so that future
versions of cFE don't modify WriteToSysLog in such a way that it would
become a problem.

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Imported from trac issue 236. Created by dcmccom3 on 2018-04-27T12:16:34, last modified: 2019-03-24T16:45:53

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Trac comment by jhageman on 2019-03-24 16:45:53:

Could relate to #237

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Sounds like the resolution should also include a requirement (and part of build verification) or at maybe a functional test that shows an syslog can be used outside of a registered app. Need to investigate path forward (may already be covered in a test?)