memcache错误码

typedef enum {
  MEMCACHED_SUCCESS,
  MEMCACHED_FAILURE,
  MEMCACHED_HOST_LOOKUP_FAILURE,
  MEMCACHED_CONNECTION_FAILURE,
  MEMCACHED_CONNECTION_BIND_FAILURE,
  MEMCACHED_WRITE_FAILURE,
  MEMCACHED_READ_FAILURE,
  MEMCACHED_UNKNOWN_READ_FAILURE,
  MEMCACHED_PROTOCOL_ERROR,
  MEMCACHED_CLIENT_ERROR,
  MEMCACHED_SERVER_ERROR,
  MEMCACHED_CONNECTION_SOCKET_CREATE_FAILURE,
  MEMCACHED_DATA_EXISTS,
  MEMCACHED_DATA_DOES_NOT_EXIST,
  MEMCACHED_NOTSTORED,
  MEMCACHED_STORED,
  MEMCACHED_NOTFOUND,
  MEMCACHED_MEMORY_ALLOCATION_FAILURE,
  MEMCACHED_PARTIAL_READ,
  MEMCACHED_SOME_ERRORS,
  MEMCACHED_NO_SERVERS,
  MEMCACHED_END,
  MEMCACHED_DELETED,
  MEMCACHED_VALUE,
  MEMCACHED_STAT,
  MEMCACHED_ITEM,
  MEMCACHED_ERRNO,
  MEMCACHED_FAIL_UNIX_SOCKET,
  MEMCACHED_NOT_SUPPORTED,
  MEMCACHED_NO_KEY_PROVIDED, /* Deprecated. Use MEMCACHED_BAD_KEY_PROVIDED! */
  MEMCACHED_FETCH_NOTFINISHED,
  MEMCACHED_TIMEOUT,
  MEMCACHED_BUFFERED,
  MEMCACHED_BAD_KEY_PROVIDED,
  MEMCACHED_INVALID_HOST_PROTOCOL,
  MEMCACHED_SERVER_MARKED_DEAD,
  MEMCACHED_UNKNOWN_STAT_KEY,
  MEMCACHED_E2BIG,
  MEMCACHED_INVALID_ARGUMENTS,
  MEMCACHED_KEY_TOO_BIG,
  MEMCACHED_AUTH_PROBLEM,
  MEMCACHED_AUTH_FAILURE,
  MEMCACHED_AUTH_CONTINUE,
  MEMCACHED_MAXIMUM_RETURN /* Always add new error code before */
} memcached_return_t;