Conversion Question

Hi Folks;

I'm running a WMI query to get the sizes of the disk drives in a computer. The result of course is a large number but I want to convert that number into a nicer format (i.e. 80G).

So this is what I have thus far:

oid GetWMITotal(HRESULT hres, IWbemServices *pSvc, char * sQuery, LPCWSTR sCol, char * data)

{

_variant_t varData;

IEnumWbemClassObject* pEnumerator = NULL;

ULONG uReturn = 1;

IWbemClassObject *pclsObj;

char cSuffix;

int iStringOp = 0;

hres = pSvc->ExecQuery(

bstr_t("WQL"),

bstr_t(sQuery),

WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,

NULL,

&pEnumerator);

HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1, &pclsObj, &uReturn);

hr = pclsObj->Get(sCol, 0, &varData, 0, 0);

INT Size = varData; // CAN'T GET DRIVE SIZE HERE

It's here that's the problem. I can get RAM size but not disk drive size. Is there something other than INT that I can use for both or do I have to create another function

if (Size >= 1000000000)

{

Size /= 1000000000;

cSuffix = 'G';

}

else if (Size >= 1000000)

{

Size /= 1000000;

cSuffix = 'M';

}

itoa(Size, data, 10);

while (data[iStringOp] != '\0')

iRAMStringOp++;

data[iStringOp] = cSuffix; data[iStringOp + 1] = '\0';

pEnumerator->Release();

pclsObj->Release();

}

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Conversion Question

Priya Shekhar

If you're requesting the field Size of the Win32_DiskDrive table, that's a uint64. This value won't fit in your INT Size, which is 32 bit. Representing the drive size with such a number would limit us to 2^32, 4294967296 or rather 4.2GB. What you have to do is use a

unsigned __int64 LargeSize = varData;
int Size;

then do your

if(LargeSize >= 1000000000)
{
Size = LargeSize / 1000000000;
cSuffix = 'G';

and so forth.
Abdullah Sowayan

Still says it can't convert _variant_t to __int64. This is what I have:

_variant_t varData;

...

HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1, &pclsObj, &uReturn);

hr = pclsObj->Get(sCol, 0, &varData, 0, 0);

__int64 Size = varData;

...

I've noticed that _variant_t can take inputs. Up until late last week I've never used it before but is there something I can do with the inputs
LievenI

Add

#define _WIN32_WINNT 0x501

to the top of your precompiled header (if any). At least be sure that this line precedes your #include <comutil.h>.
SoniaJulka

I've got to blame this one on the temperature. My error reading abilities are melting away

__int64 LargeSize = (__int64)varData; ought to do the trick.
robinjam

It says cannot convert from '_variant_t' to unsigned __int64. What am I missing
Chimme
Maybe the heat is messing up my computer since it still insists 'type cast' : cannot convert '_variant_t' to '__int64'
Kestutis

Viorel. wrote:

It seems that you are working with VC 6.0. In this case __int64 is not supported by _variant_t. Try long type instead.

#if (_WIN32_WINNT >= 0x0501)
_variant_t(__int64 i8Src) throw(); // Creates a VT_I8
_variant_t(unsigned __int64 ui8Src) throw(); // Creates a VT_UI8
#endif

That's what gave him a hard time. I was puzzled by why the variant was so reluctant to pick the right extractor operator.. This somewhat explains it.
Davids Learning
That seemed to work! Thanks!
Dracosveen
Try removing the "unsigned" prefix of your __int64.
ozhonetech
It seems that you are working with VC 6.0. In this case __int64 is not supported by _variant_t. Try long type instead.
Conversion Question

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