gnupg: Agent GETEVENTCOUNTER
2.6.15 Get the Event Counters
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GETEVENTCOUNTER
This function return one status line with the current values of the
event counters. The event counters are useful to avoid polling by
delaying a poll until something has changed. The values are decimal
numbers in the range '0' to 'UINT_MAX' and wrapping around to 0. The
actual values should not be relied upon; they shall only be used to
detect a change.
The currently defined counters are:
'ANY'
Incremented with any change of any of the other counters.
'KEY'
Incremented for added or removed private keys.
'CARD'
Incremented for changes of the card readers stati.