doc/sdk/io-guide/guide-to-cache-api/how-to-do-a-cache-write.en.rst

How to Do a Cache Write
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Use ``TSCacheWrite`` to write to a cache (see the `sample Protocol
plugin <../../new-protocol-plugins#AboutSampleProtocol>`__). Possible
callback events include:

-  ``TS_EVENT_CACHE_WRITE_READ`` - indicates the lookup was successful.
   The data passed back along with this event is a cache vconnection
   that can be used to initiate a cache write.

-  ``TS_EVENT_CACHE_OPEN_WRITE_FAILED`` - event returned when another
   continuation is currently writing to this location in the cache. Data
   payload for this event indicates the possible reason for the write
   failing (``TSCacheError``).