C / C++ / MFC Discussion Boards

sashoalm wrote:
This is an MFC forum.

Not exactly, it is C/C++/MFC, so his question is (sort of) acceptable.

txtspeak is the realm of 9 year old children, not developers. Christian Graus

You may

install sqlite3.
include sqlite3.h in your source file(s).
compile specifying -lsqlite3.

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Finally got it working ! thanks guys.

You are welcome. Have a nice ubuntu-sqlite experience (I'm using that pair too)!
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

I am getting unexpected results due to my lack of understanding of static const initialization. Basically, I thought the rule is that static const members are initialized in the order in which they are declared (just like member variables). However, I have some code that is yielding unexpected results, which I have copied below to illustrate the issue.

// Common.h
#pragma once
#ifndef COMMON_H
#define COMMON_H

typedef unsigned __int8  __uint8 ;
typedef unsigned __int16 __uint16;
typedef unsigned __int32 __uint32;
typedef unsigned __int64 __uint64;

// Template structures used to get information about IEEE floating-point formats
template<size_t bytes> struct __float {
public:
    // Mantissa size, in bits
    static const __uint8  MantissaSize;
    // Significand size, in bits
    static const __uint8  SignificandSize;
    // Exponent size, in bits
    static const __uint8  ExponentSize;
    // The maximum representable exponent (reserved for inf and NaN)
    static const __uint16 ExponentMax;
    // The exponent bias
    static const __uint16 ExponentBias;
    // An integer with only the bit left of the mantissa set
    static const __int64 SignificandBit;
    // An integer with all bits included in the mantissa set
    static const __int64 MantissaMask;
    static const __int64 SignificandMask;
    // An integer with all bits included in the exponent set
    static const __int64 ExponentMask;
};
    
// Defines the constants used by the __float structure
template<> const __uint8 __float< 2>::MantissaSize =  10;
template<> const __uint8 __float< 4>::MantissaSize =  23;
template<> const __uint8 __float< 8>::MantissaSize =  52;
    
// Compute the constants for the __float structure
template<size_t bytes>
const __uint8  __float<bytes>::SignificandSize = __float<bytes>::MantissaSize + 1;
template<size_t bytes>
const __uint8  __float<bytes>::ExponentSize    = (bytes << 3) - __float<bytes>::SignificandSize;
template<size_t bytes>
const __uint16 __float<bytes>::ExponentMax     = (1 << __float<bytes>::ExponentSize) - 1;
template<size_t bytes>
const __uint16 __float<bytes>::ExponentBias    = __float<bytes>::ExponentMax >> 1;
template<size_t bytes>
const __int64 __float<bytes>::SignificandBit  =
    static_cast<__int64>(1) << __float<bytes>::MantissaSize;
template<size_t bytes>
const __int64 __float<bytes>::MantissaMask    =
    __float<bytes>::SignificandBit - 1;
template<size_t bytes>
const __int64 __float<bytes>::SignificandMask =
    __float<bytes>::SignificandBit | __float<bytes>::MantissaMask;
template<size_t bytes>
const __int64 __float<bytes>::ExponentMask    =
    static_cast<__int64>(__float<bytes>::ExponentMax) <<
    __float<bytes>::MantissaSize;
    
#endif

And now, the main function:

// Main.cpp
#include <iostream>
#include "Common.h"

using namespace std;

double getOnePointFive() {
    __uint64 rval(0);
    rval = (static_cast<__uint64>(__float<8>::ExponentBias) << __float<8>::MantissaSize) |
           (1ULL << (__float<8>::MantissaSize - 1));
    return *reinterpret_cast<double*>(&rval);
}
    
int main(int argc, const char* argv[]) {
    cout << getOnePointFive() << endl;
    cout << __float<8>::ExponentBias << endl;
    cin.get();
    return 0;
}

When this runs, I would expect to get the result 1.5, and the value of __float<8>::ExponentBias should be 0x3FF. However, I am getting zero for the ExponentBias value which results in the subnormal value 3*2^-1024. Why is the value of ExponentBias coming out as zero? Thanks,

Sounds like somebody's got a case of the Mondays

-Jeff

static const integrals are initialized inside their class.
Take a look at this - Initializing const static Data Members[^]

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

Yes, I saw that post in my quest for a solution, but I can't figure out how to go about initializing the members based on template specialization. Any ideas?

Oh, I also get the compiler error C2057 when I move all of the non-specialized declarations within the structure definition. In other words, I attempted the following:

// Template structures used to get information about IEEE floating-point formats
template<size_t bytes> struct __float {
public:
    // Mantissa size, in bits
    static const __uint8  MantissaSize;
    // Significand size, in bits
    static const __uint8  SignificandSize = MantissaSize + 1;
    // Exponent size, in bits
    static const __uint8  ExponentSize    = (bytes << 3) - SignificandSize;
    // The maximum representable exponent (reserved for inf and NaN)
    static const __uint16 ExponentMax = (1 << ExponentSize) - 1;
    // The exponent bias
    static const __uint16 ExponentBias = ExponentMax >> 1;
    // An integer with only the bit left of the mantissa set
    static const __int64 SignificandBit = 1LL << MantissaSize;
    // An integer with all bits included in the mantissa set
    static const __int64 MantissaMask = SignificandBit - 1;
    static const __int64 SignificandMask = SignificandBit | MantissaMask;
    // An integer with all bits included in the exponent set
    static const __int64 ExponentMask = static_cast<__int64>(ExponentMax) << MantissaSize;
};
    
// Defines the constants used by the __float structure
template<> const __uint8 __float< 2>::MantissaSize =  10;
template<> const __uint8 __float< 4>::MantissaSize =  23;
template<> const __uint8 __float< 8>::MantissaSize =  52;

This resulted in a number of C2057 errors about expecting a constant expression. I must be misinterpreting your recommendation, because I can't figure out how to make such a thing compile. Thanks for any additional help,

Sounds like somebody's got a case of the Mondays

-Jeff

modified on Tuesday, February 16, 2010 9:45 AM

OK... I found a pretty good thread here[^] that talks about initialization of static const template members. I still don't understand why the code I originally posted doesn't work, but I did see a statement in this post that clearly indicated that all compile-time constant initialized static const members are performed prior to all dynamically initialized static members. Therefore, I decided to remove the dependencies on all dynamically defined static const members, instead repeating the math based on MantissaSize which is ALWAYS (according to the referenced post) defined prior to the other members. Now when I run, I no longer get any errors, and instead get the intended result. I copied my new code below:

// Template structures used to get information about IEEE floating-point formats
template<size_t bytes> struct __float {
public:
    // Mantissa size, in bits
    static const __uint8  MantissaSize;
    // Significand size, in bits
    static const __uint8  SignificandSize;
    // Exponent size, in bits
    static const __uint8  ExponentSize;
    // The maximum representable exponent (reserved for inf and NaN)
    static const __uint16 ExponentMax;
    // The exponent bias
    static const __uint16 ExponentBias;
    // An integer with only the bit left of the mantissa set
    static const __int64 SignificandBit;
    // An integer with all bits included in the mantissa set
    static const __int64 MantissaMask;
    // An integer with all bits included in the mantissa set,
    //   as well as the bit left of the mantissa
    static const __int64 SignificandMask;
    // An integer with all bits included in the exponent set
    static const __int64 ExponentMask;
};
    
// Defines the constants used by the __float structure
template<> const __uint8 __float<2>::MantissaSize = 10;
template<> const __uint8 __float<4>::MantissaSize = 23;
template<> const __uint8 __float<8>::MantissaSize = 52;
    
// Compute the constants for the __float structure
template<size_t bytes>
const __uint8  __float<bytes>::SignificandSize = __float<bytes>::MantissaSize + 1;
template<size_t bytes>
const __uint8  __float<bytes>::ExponentSize    =
    (bytes << 3) - __float<bytes>::MantissaSize - 1;
template<size_t bytes>
const __uint16 __float<bytes>::ExponentMax     =
    (1 << ((bytes << 3) - __float<bytes>::MantissaSize - 1)) - 1;
template<size_t bytes>
const __uint16 __float<bytes>::ExponentBias    =
    (1 << ((bytes << 3) - __float<bytes>::MantissaSize - 2)) - 1;
template<size_t bytes>
const __int64 __float<bytes>::SignificandBit   =
    1LL << __float<bytes>::MantissaSize;
template<size_t bytes>
const __int64 __float<bytes>::MantissaMask     =
    (1LL << __float<bytes>::MantissaSize) - 1;
template<size_t bytes>
const __int64 __float<bytes>::SignificandMask  =
    (1LL << (__float<bytes>::MantissaSize + 1)) - 1;
template<size_t bytes>
const __int64 __float<bytes>::ExponentMask     =
    ((1LL << ((bytes << 3) - __float<bytes>::MantissaSize - 1)) - 1)
    << __float<bytes>::MantissaSize;

Again, if anyone can explain why my initial code didn't work I would really appreciate it. Thanks,

Sounds like somebody's got a case of the Mondays

-Jeff

Hi,

How to drag image list from one window to another window in MFC MDI application.

Thanks & Regards,
Ratheesh.

Hi All,

I am using one com dll and have multiple clients on the same machine which are creating pointers for same interface, so is there can be any conflict.

Example:

SomeComComponentLib::IsomeInterface objInterfaceptr;

.....create instance

Now all the client applications are using objInterfaceptr in same way...Please provide me some suggestion to avoid conflict.

Thanks A Ton
Ash_VCPP
walking over water is just knowing where the stones are.....

What conflict?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Actually i want to ask that can it cause any coflict...

in my situation:

Some times i am not able to use the method of the interface object.

like application doesnt acknowledge the object and returns without performing the task.

Thanks A Ton
Ash_VCPP
walking over water is just knowing where the stones are.....

Ash_VCPP wrote:
Actually i want to ask that can it cause any coflict...

I suppose not (but, without code, is a blind guess).

Ash_VCPP wrote:
Some times i am not able to use the method of the interface object.

like application doesnt acknowledge the object and returns without performing the task.

What do you mean with: "application doesn't acknowledge the object?". Do you get errors?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Ok let me explain you the problem in detail...

i am using msscript.ocx to get script support, now i am using one com dll and using its interface and adding interface object in script object, now script is using these object without initializing it, now i have same application running multiple times on same machine repeating the process, but some times vbscript doesnt acknoledge the interface objects.

Example:

m_ScriptObj.AddObject("DataIn", DataIn, false);
m_ScriptObj.AddObject("DataOut", DataOut, false);
m_ScriptObj.AddObject("Parser", Parser, false);
m_ScriptObj.AddObject("Setting", Setting, false);

now suppose i am using DataIn object inside my vbscript, and here comes the Inconsistent behaviour.

Thanks A Ton
Ash_VCPP
walking over water is just knowing where the stones are.....

Unfortunately it looks like there is no documentation about the script control (or I am not able to find it...). I have used it in the past, but I never needed the AddObject method.
Frown | :(

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Hi all,

I want to write a code in which i want to change the icon of an exe i.e user will provide a icon at runtime and when he will click on change button the icon should be the new one....

How can i do this...

Thanks in advance

Try with UpdateResource[^]. Please note that using this will not actually update the already loaded resources in memory (meaning using UpdateResource to change the icon inside the exe will not magically change the icon you see in the top-left corner of the application's window for example to the new one, you will have to do that yourself, maybe by broadcasting some message to your windows to re-load the icon or such), however if you then quit and re-start the program the new icon should appear (also the new icon should be displayed in explorer and so...you might also need to do something to make explorer notice the change, am not sure about that...).

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

I dont know how to do this but ToDoList[^] does that during Time Tracking. Maybe you can look at its source and figure it out.

-Saurabh

Hi all

How can i Insert data of more than 4000 characters in clob datatype in oracle database?
I use this query to insert data.

INSERT INTO testing VALUES(utl_raw.cast_to_raw('SomeDATA'));

Then i am getting error

OraOLEDB Error: -2147217900
ORA-01704: string literal too long
IDispatch error #3092

Please help me

MsmVc wrote:
INSERT INTO testing VALUES(utl_raw.cast_to_raw('SomeDATA'));

Have you tried replacing this with a string literal to see at what point it fails, something like:

INSERT INTO testing VALUES("12345678901234567890");

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"Man who follows car will be exhausted." - Confucius

Thanks for reply
i try to this and i found when data is more that 2000 thousand then i am getting error.

INSERT INTO testing VALUES(utl_raw.cast_to_raw('0x151c2f'));

ORA-06502: PL/SQL: numeric or value error: raw variable length too long
ORA-06512: at "SYS.UTL_RAW", line 224

See if the first two results from this search are of any help.

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"Man who follows car will be exhausted." - Confucius

Hi guys,
Looking for some help...

In my application using VS2008 (MFC 9.0) + SP1, i encountered an error and i felt that it is of the MFC/Framework.
I am giving a very simple scenerio, and i hope amy body may reproduce it easyly.
Follow these steps: -
1. Create a new MFC Application Project.
2. The type i choose is MultiDoc Application with Doc/View Support and Office Project Style and Ribbon Menu
Here my View is derived from CScrollView.

Now i Run the Application and changed the theme, say to Silver and now i hibernated the PC. After Starting the PC i got that the application is in the default theme (BLUE). However as i checked the selected style in the menu, its still the Silver.
I an expecting any boddy will help me soon.

Regards
Harsh

HARSH

Programmers are in a race with the Universe to create bigger and better idiot-proof programs, while the Universe is trying to create bigger and better idiots. So far the Universe is winning.

The CMFCVisualManagerOffice2007 reset any style to its default
const CMFCVisualManagerOffice2007::Style c_StyleDefault = CMFCVisualManagerOffice2007::Office2007_LunaBlue; value after the restart...

It would be not the case
when you would set your own (derivated) VisualManager
with the overwritten function virtual void OnUpdateSystemColors() Smile | :)

Thanks Eugen,
I'll try n let you know..

HARSH

Programmers are in a race with the Universe to create bigger and better idiot-proof programs, while the Universe is trying to create bigger and better idiots. So far the Universe is winning.