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pointer to pointer

Posted on 2009-03-30
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Last Modified: 2012-05-06
Hello
I'm trying to use a NI library function that is decleard as below.
CWUIControlsLib_CWAxisGetFormatString (CAObjHandle objectHandle,
                                                       ERRORINFO *errorInfo,
                                                       char **returnValue);
The purpose is to read out a format string in "returnValue".
If I declear a pointer to pointer to char as char **Pointer, the compiler (CVI 8.5) complains
that the pointer is not initialized and I do not get the sting I'm looking for.
Anyone have a proposal ?
Regards Per
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Question by:fluidtronic
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Expert Comment

by:ozo
ID: 24018065
can you initialize the pointer?
if it is a pointer in which to return a value, you may want to point it to the place where you want the value returned.
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Accepted Solution

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twocandles earned 50 total points
ID: 24018093
try to declare it as this:

char *returnValue[MAX_VALUE];

thus initializing it.
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Author Comment

by:fluidtronic
ID: 24018110
Hi
I have tried this but with the same result.

char **Specifier,FormatString[80];
*Specifier=FormatString;       
CWUIControlsLib_CWAxisGetFormatString(Axis[0],NULL,Specifier);
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Author Closing Comment

by:fluidtronic
ID: 31564293
That works. Thank you.
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LVL 6

Expert Comment

by:twocandles
ID: 24018477
You're welcome. Thanks for the points!
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