Description:
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I have developed a database access layer that tries to ensure that proper result handling is provided for.

However, when using persistant connections I have the problem that whenever the database service fails (due to intermediate shutdown or other network related problems), the persistantly opened connection link to the database service does not revalidate its connection and as such will report a mysql_error() state of naught and as such it cannot be determined exactly as to where the error stems from.



Reproduce code:
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I will not post any line of source code here, just an indepth explanation of how to reproduce:

start your mysql daemon.

open a persistant connection to the service.

do something with the connected and selected database.

shutdown the mysql daemon.

try to re-use the persistant connection using mysql_pconnect() and try to send a query to the service.

The query will fail, but there will not be any result code given by mysql_errno() that will provide any hint on the actual cause of the failure.


Expected result:
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My code should produce a DbConnectionFailure instead of simply an DbUnexpectedFailure or DbUnknownFailure in case the persistant connection to the database fails because of the database service being no longer available.

Actual result:
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DbUnknownFailure.

mysql_errno() fails to report error state.