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Anonymous wrote:
how much memory does a pointer takes?
in Win32, the pointer itself takes 4 bytes (32 bits).
I'm not the droid you're looking for.
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How big are the instances?
Needs this big list to be whole in memory?
Have you considered using a database?
Will be the elements deleted or reordered at runtime (the pointers or indexes could become invalid by concurrent access)?
The indexes would be unefficient if you implent the list as a linked one.
Anonymous wrote:
Inshort how much memory does a pointer takes?
It depends on HW platform - on Intel's IA32 it's 4 bytes.
Anonymous wrote:
Is it dependent on the size of the object being pointed to?
No, it's only adress in memory.
Anonymous wrote:
How much memory does a pointer need? like an integer needs 1 byte etc....
size of an integer depends on platform and type. Size of int type depends on platform. You can use types as BYTE, WORD, DWORD ... of deterministic size.
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In 32-bit windows (Win95+) an int takes 4 bytes (32 bits), and in the same environment a pointer also takes 4 bytes. (a pointer is nothing more than an unsigned int pointing to a memory address)
- Anders
Money talks, but all mine ever says is "Goodbye!"
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Anonymous wrote:
I have list of a big object.The approximate elements of this list is expected to the tune of 10,000,000-99,000,000.
If this was to be "I have a list of big objects", and not "a big object", it means the object(s) at hand can only be (on avg) less than 20 bytes (incl. overhead the object can probably be no larger than 12-16 bytes). That's not such a large object.
However, it seems you have a devilish large number of instances of such objects!
Now if I have to use only part of this big list in another object.
Would it be advisable to use a list of pointers to this list section or use a list of the index values of the section?
In Win32 it wouldn't matter, since you'd need a 32-bit entity to express an index>64K, and that's the size needed to express a 32-bit pointer (where are you from to not know this?).
In reality, in Win32, it wouldn't matter at all what you did - you'd be out of memory (address space) before you could do anything sensible with that amount of data.
My suggestion is you either memory-map it in smaller units, or use a computer architecture designed to handle this amount of data (SGI, Cray and Tandem comes to mind).
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I have an ClistCtrl in my dialog.How can I get the texts of item an its subitem when user click on an item?I overriden NM_DBLCLK but I can't get the texts of them!
Mazy
"And the carpet needs a haircut, and the spotlight looks like a prison break
And the telephone's out of cigarettes, and the balcony is on the make
And the piano has been drinking, the piano has been drinking...not me...not me-Tom Waits
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Why do you even mention duouble-click when you say you only want the selection? How about selchange (or similar)?
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Nope,I want when user double click on an item.Whats the way for that?
Mazy
"And the carpet needs a haircut, and the spotlight looks like a prison break
And the telephone's out of cigarettes, and the balcony is on the make
And the piano has been drinking, the piano has been drinking...not me...not me-Tom Waits
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From what I can understand from MSDN Library, loadXML of IXMLDOMDocument return a S_FALSE (I think it was) if the load failed, but it also has a VARIANT_BOOL varible as a parameter which also return FALSE if the load failed. I'm confused...
What is the difference between the HRESULT value and the VARIANT_BOOL value?
Which one should I check?
Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!
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A VARIANT_BOOL is the Automation version of bool. Its possible values are VARIANT_TRUE and VARIANT_FALSE. In the case of loadXML(), the bool tells you whether the load succeeded or failed. If you need to know why it failed, then you can check the HRESULT.
--Mike--
When 900 years old you reach, look as good you will not. Hmm.
1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click!
My really out-of-date homepage
Sonork-100.19012 Acid_Helm
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In VC6 there is Resource symbols... command in View menu, should be something similar in VC.NET. Or you can define a menu resource with the commands.
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I want to find out that how much memory my program is consuming at certain point of execution. How can i find it ???? Actualy the application i developed, is multithreaded and at many occasions, memory is selected from the heap and returned back. I want to find out that how much memory (complete i.e stack+ heap+ etc ) is under consumption by my program. Plesae tell me ???
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CTRL+ALT+DEL and look in the process list of the windows task manager for your program? There is a tab "Memory usage"...
-----
We are what we repeatedly do. Excellence, then, is not an act, but a habit.
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GetProcessWorkingSetSize might help.
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Hello,
I ran into the following problem in my Unicode project. I have a FileName of the type unsigned short* and I'm willing to extract the extension and compare it. I use the following code:
==
unsigned short* FileExt = new unsigned short[10];
int FileNameLen = wcslen(FileName);
for(int x = FileNameLen; x >= 0; x--)
{
if(FileName[x] == '.')
{
// Get the extension
wcsncpy(FileExt, FileName + x + 1, FileNameLen - x - 1);
break;
}
}
FileExt = _wcsupr(FileExt);
if(FileExt == _T("U") || FileExt == _T("DLL"))
{
return 1;
}
else if(FileExt == _T("UNR"))
{
return 2;
}
else
{
return 3;
}
===
First of all, it ALWAYS returns 3, none of the other IFs are triggered for some reason.
Second, if I view the FileExt after the extraction; if the extension of the file is only ONE charachter, it adds a strange other char to it for no apparent reason...
Can anyone tell me what I'm doing wrong?
Thanks,
- Fahr
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Try this:
_TCHAR *FileExt = new _TCHAR[10];
int FileNameLen = _tcslen(FileName);
for(int x = FileNameLen; x>= 0; x--)
{
if(FileName[x] == _T('.'))
{
_tcsncpy(FileExt, FileName + x + 1, FileNameLen - x - 1);
break;
}
}
_tcsupr(FileExt);
if ((_tcscmp(FileExt,_T("U")) == 0) || (_tcscmp(FileExt,_T("DLL")) == 0))
{
delete []FileExt;
return 1;
}
else if (_tcscmp(FileExt,_T("UNR")) == 0)
{
delete []FileExt;
return 2;
}
else
{
delete []FileExt;
return 3;
}
First, I replaced the 'unsigned short' with _TCHAR. You're using the tchar.h macros elsewhere, so this will make the code work whether you compile for MBCS or UNICODE. Second, the first if condition wasn't quite right; I changed the character constant from '.' to _T('.'). The '.' is an MBCS character always, even if you are compiling for UNICODE. The statement FileExt = _wcsupr(FileExt) will make the FileExt value upper case, but it may also change the value of FileExt (which you probably don't want). Next, the conditions where you compare the extracted extension weren't right. Using FileExt == _T("U") compares the pointer to the extension value to the pointer to a constant string. You want to do a string comparison here, hence the _tcscmp calls. I also added the delete's before the return's so that this wouldn't leak memory.
Software Zen: delete this;
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Ok, since I'm compiling only unicode I stuck with the wcs commands (Unicode is required for this, I'm not ever going to recompile it in MBCS). If there's a good reason for me to use the _TCHAR and _tcs commands instead, please tell me 
The code DOES work now with the compare calls and the not writing back after uppercasing, but the 1-letter-extension problem still remains for some reason, after a one-letter extension it adds a 135-char... I don't get why...
As for the delete[]s, what to do in such a case if I want to RETURN the FileExt? I can't delete it before the return. And also, what to do with static variables? I assume I can't delete those either...
Thanks,
- Fahr
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You have a couple of problems. First, the correct type for Unicode characters is WCHAR (yeah, it's the same thing as unsigned short due to a typedef, but using WCHAR will make the code easily readable by others). Then you're comparing strings with == which is not correct for C-style strings.
There's already an API for finding the extension, then once you have that use _wcsicmp() to do case-insensitive comparison.
int LookAtExt(LPCWSTR wszFilename)
{
LPCWSTR wszExt = PathFindExtension ( wszFilename );
if ( 0 == _wcsicmp ( wszExt, L".U" ) || 0 == _wcsicmp ( wszExt, L".DLL" ) )
return 1;
else if ( 0 == _wcsicmp ( wszExt, L".UNR" ) )
return 2;
else
return 3;
}You can also use a string wrapper class like wstring or CString (which has a handy CompareNoCase() method) to make the code a little neater.
--Mike--
When 900 years old you reach, look as good you will not. Hmm.
1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click!
My really out-of-date homepage
Sonork-100.19012 Acid_Helm
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PathFindExtension results in:
error LNK2001: unresolved external symbol __imp__PathFindExtensionW@4
I DO have shlwapi.h in my includes...
- Fahr
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OK! That worked! Thanks a lot
It saves a lot of trouble of getting it myself, plus the weird trailing char error is no longer there
Also, you suggested the use of L"", while I use _T(""), a quick look in the TCHAR.h gave me the idea that _T("") is defined as L""... So what IS the actual difference? If any...
- Fahr
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Use the TCHAR macros (including _T) when you want to make ANSI and Unicode builds from the same code. Since you said you only need to make a Unicode build, you can go ahead and use L"" to make Unicode literals.
See my article on Win32 Character Encodings[^] for the full scoop.
--Mike--
When 900 years old you reach, look as good you will not. Hmm.
1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click!
My really out-of-date homepage
Sonork-100.19012 Acid_Helm
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Well, that article does shed light on a lot of issues, thanks a lot
I actually DO need the DLL to run under Windows 98, if I use only unicode it wont work then I guess? I didn't quite realise that...
So what do I do now? Change all my L""s back to _T("")s and all my WCHAR*s to TCHAR*s?
Will that do the trick? And do I need to build 2 different DLLs for WinNT and Win9x??
- Fahr
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Fahr wrote:
I actually DO need the DLL to run under Windows 98, if I use only unicode it wont work then I guess?
Right. You can use Unicode strings in 98, however you can't call Unicode APIs because they are not implemented. So yeah, you'll need to change your wcsxxx() calls to their _tcsxxx() equivalents, and use _T around literals. The string article covers this topic and why the TCHAR system is necessary.
It sounds like you're not using any NT-specific features, so you can just build an MBCS build of your code and use that on NT. Again, see the string article for the full story.
--Mike--
When 900 years old you reach, look as good you will not. Hmm.
1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click!
My really out-of-date homepage
Sonork-100.19012 Acid_Helm
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yeah, I changed all it around...
problem is tho, as soon as I change UNICODE,_UNICODE to _MBCS, I get about 5 unresolved externals...
I'm using the DLL for native coding with Unreal Script, the script can call to the DLL and uses the core and engine of the game for game-specific functions, apperently those only support unicode...
Which is terribly odd, cuz the game runs on ANY windows...
- Fahr
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