https://sourceforge.net/p/perfcache/wiki/RetrieveDataLength%2520Method/Recent changes to RetrieveDataLength MethodenThu, 15 Dec 2011 19:25:07 -0000https://sourceforge.net/p/perfcache/wiki/RetrieveDataLength%2520Method/<pre>--- v1 +++ v2 @@ -18,36 +18,25 @@ 1) szKey or wszKey: the key - 2) pbData: a pointer to a buffer of bytes that will be inserted into the cache. - - 3) cbData: a count of bytes of the data. This value does not necessarily need to include - space for a trailing NULL. Exactly cbData bytes of the buffer pointed to by pbData - will be stored in the cache. - - 4) numSecondsTTL: number of seconds for the "time-to-live" value. - -<br /> + 2) pcbData: pointer to a variable that on return will contain the exact number of bytes of the data that is stored in the cache entry. + +<br /> ###### Return values:###### E_KEY_INVALIDKEYTYPE E_INVALID_KEYVALUE E_KEY_NOTFOUND E_CACHE_RETRIEVE_ENTRY_MARKED_FOR_DELETION E_CACHE_RETRIEVE_ENTRY_IS_EXPIRED E_SUCCESS <br /> ###### Remarks:###### -The RetrieveDataLength() method - -RetrieveDataLength() retrieves the length of a cache entry's Document field's -data, in bytes. This function includes internal synchronization; it performs a -directory lookup followed by a retrieval of the data length field from the -cache entry's Document member field. - If the original data that was inserted into the cache had contained a null terminator byte, the count returned in *pcbData will include space for this trailing byte. + +RetrieveDataLength() includes internal synchronization; it performs a directory lookup followed by a retrieval of the data length field from the cache entry's Document member field. If the key is not found (E_KEY_NOTFOUND), RetrieveDataLength() will increment the global miss count. However, if the key is found and the function is successful, </pre>Glenn HoffordThu, 15 Dec 2011 19:25:07 -0000https://sourceforge.netccfa44899ed775b8c276ee9212dc08a21135d1fehttps://sourceforge.net/p/perfcache/wiki/RetrieveDataLength%2520Method/##### Method: Cache::RetrieveDataLength ##### ###### Summary: ###### RetrieveDataLength() retrieves the length in bytes of a cache entry's Document field's data. <br /> ###### Syntax: ###### int RetrieveDataLength (const QBYTE *szKey, size_t *pcbData); int RetrieveDataLength (const QWORD *wszKey, size_t *pcbData); <br /> ###### Parameters:###### 1) szKey or wszKey: the key 2) pbData: a pointer to a buffer of bytes that will be inserted into the cache. 3) cbData: a count of bytes of the data. This value does not necessarily need to include space for a trailing NULL. Exactly cbData bytes of the buffer pointed to by pbData will be stored in the cache. 4) numSecondsTTL: number of seconds for the "time-to-live" value. <br /> ###### Return values:###### E_KEY_INVALIDKEYTYPE E_INVALID_KEYVALUE E_KEY_NOTFOUND E_CACHE_RETRIEVE_ENTRY_MARKED_FOR_DELETION E_CACHE_RETRIEVE_ENTRY_IS_EXPIRED E_SUCCESS <br /> ###### Remarks:###### The RetrieveDataLength() method RetrieveDataLength() retrieves the length of a cache entry's Document field's data, in bytes. This function includes internal synchronization; it performs a directory lookup followed by a retrieval of the data length field from the cache entry's Document member field. If the original data that was inserted into the cache had contained a null terminator byte, the count returned in *pcbData will include space for this trailing byte. If the key is not found (E_KEY_NOTFOUND), RetrieveDataLength() will increment the global miss count. However, if the key is found and the function is successful, the global hit count is not incremented, since a successful call to RetrieveDataLength() is normally followed by a call to Retrieve(). RetrieveDataLength() does not modify Replacement metadata (e.g. LRU, LFU). <br /> ###### Example ###### size_t cbData = 0; int iResult = pCache->RetrieveDataLength ((const QBYTE *) "AAA", // key &cbData); if (iResult != E_SUCCESS) { // error handling here } Glenn HoffordThu, 15 Dec 2011 19:21:29 -0000https://sourceforge.netbc9f26bc41d7eb5db4c08cb545ff1b531d966d3b