Message state updates
The ozekimessageout table has a field called "status". This field contains information about the state of the outgoing message.
When a new message needs to be sent, the status field should be set to "send". This value indicates that the SMS should be downloaded from the outgoing message table for delivery by Ozeki Message Server 6.
After this download happens Ozeki will update the status to "sent", to make sure the next time this message is not downloaded again. If the message is in the "sent" state it means it is waiting in the outgoing message queue of Ozeki, but it is not yet sent to the provider.
If the GSM service provider accepts the message it's state is updated to "transmitted".
If the message is not accepted by the provider for delivery, for example due to an invalid telephone number, the state is changed to "deleted".
In some situations the provider can send a delivery report back to the system if the message is successfully delivered to the destination phone. In this case the message state is changed to "received" from "transmitted".
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