Is there a proper way to return either no data, or mark an external check as not supported.
Consider a text field polling while the host is not available. Returning blank is not appropriate, I would rather return no data (i.e. there would be no data stored), or would be happy to mark it not supported, but there seems to be no mechanism for that.
The only work around I've found is sleep long enough to time out, which is a bit ugly (and keeps the polling routine tied up, and also is a bit iffy if someone changes the timeout).
For numerics I can return non-numeric data to mark it unsupported, but for character?
The other semi-workaround is to use zabbix_sender with zabbix traps, but at least one item has to poll to get the external check to fire, so this works if your routine needs to return multiple values at least one numeric (make that the external check value, return the rest with sender).
But for a single item that is character... I don't see a way?
Consider a text field polling while the host is not available. Returning blank is not appropriate, I would rather return no data (i.e. there would be no data stored), or would be happy to mark it not supported, but there seems to be no mechanism for that.
The only work around I've found is sleep long enough to time out, which is a bit ugly (and keeps the polling routine tied up, and also is a bit iffy if someone changes the timeout).
For numerics I can return non-numeric data to mark it unsupported, but for character?
The other semi-workaround is to use zabbix_sender with zabbix traps, but at least one item has to poll to get the external check to fire, so this works if your routine needs to return multiple values at least one numeric (make that the external check value, return the rest with sender).
But for a single item that is character... I don't see a way?