Running zabbix_get I would expect to either get a valid metric or an error but sometimes all I get is a blank line (empty result), even for keys which I know never has a blank value.
The return code of zabbix_get after a empty result is 0, which does not indicate an error.

If empty result is a valid result,I suggest the resolution to this issue is updating the documentation at http://www.zabbix.com/documentation/2.0/manpages/zabbix_get to explain the scenario

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