Description

This returns nil when no error is encountered by the client, and the response status returned by the memcache server is StatusNoError. Otherwise, this returns an error.

NOTE: 1. For get requests, this also returns nil when the response status

StatusKeyNotFound.

2. For stat request, this returns the first error encountered (or nil

if there were no errors).

3. If the client is sharded, flush/stats/version/verbosity requests

will return the first error encountered (or nil if there were no
errors).