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Error 234 with CRegKey. Empty String values.

Posted on 1998-10-20
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Last Modified: 2008-03-10
When I use CRegKey.QueryValue I get the correct number of letters in the string, but my LPTSTR is always empty. The error that is returned is 234 which is ERROR_MORE_DATA. What does this mean? And why does it only do half of what it's supposed to do?

//Here is the line (note, opening the key is ERROR_SUCCESS):
error_num = key.QueryValue(lpStringVal, "LocalService", &dwStringSize);

//dwStringSize is 39 (the correct number)
//but lpStringVal is empty.
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Question by:xxchange
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Accepted Solution

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dirty_dog earned 200 total points
ID: 1175653
You need to initialize dwStringSize to the maximum number of letters that lpStringVal can hold.  Then QueryValue will replace it with the letters actually read.

This allows you to query the value once with 0 bytes, allocate enough memory to hold the value, and then query again for the actual value.
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by:xxchange
ID: 1175654
Thanks alot. Worked like a charm. You rock.


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