|
Back with 16-bit Windows, memory was addressed as segment:offset. You had "far" memory and "near" memory. That is no longer the case with 32-bit Windows. The preprocessor redefines both near and far to empty.
"Ideas are a dime a dozen. People who put them into action are priceless." - Unknown
|
|
|
|
|
Thanks David. Could you be a little more specific about near and far? I'm interested to know the difference between them back in Win16. Does it differ in Win32 today?
Thanks
|
|
|
|
|
The near/far difference is related to real-mode memory addressing on x86 CPUs. Pointers were 16 bits but you also had a 16-bit "segment" that determined which 64K block of memory a pointer was referring to. A near pointer was just the 16-bit offset, and could only point within the same segment. A far pointer was a segment+offset together, and could hold the address of any place in memory.
In Win32 protected mode, all that goes away. A pointer is a plain 32-bit address and near/far are anachronisms now. Pointers are of course 64 bits in Win64.
--Mike--
Visual C++ MVP 
LINKS~! Ericahist | 1ClickPicGrabber | CP SearchBar v2.0.2 | C++ Forum FAQ
Strange things are afoot at the U+004B U+20DD
|
|
|
|
|
The Intel 8086 architecture used a segmented memory model, where each segment spans 64K bytes. "Near" pointers are two-byte values with an offset from a fixed segment pointer and can access only a single 64K segment. "Far" pointers are 4-byte values with a 2-byte segment pointer and a 2-byte offset and can access the lower 1 MB of memory (because the memory manager's address calculation shifts the segment pointer 4 bits before adding the offset). "Huge" pointers, which are four-byte values are actual four-byte addresses and can access any area of memory by copying through a window created by a memory manager.
In the old (20 years ago  ) days, the Microsoft C compiler supported several executable targets: tiny (all code and data with in the same 64 K segment, required for COM format executables), small (code and data in separate 64 K segments), medium (far pointers for code, near pointers for data), compact (near pointers for code, far pointers for data), large (far pointers for both code and data), and huge (far pointers for code, data and static data).
/ravi
My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com
|
|
|
|
|
Everything you ever needed to know about near and far 
Ryan "Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"
|
|
|
|
|
What does FAR FAR mean, as in "A long time ago in a galaxy FAR FAR away"?
Can I access the value a variable had ten minutes ago on a different computer on the wide area network if I use the "long time ago in a galaxy FAR FAR away" syntax? 
|
|
|
|
|
Ryan "Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"
|
|
|
|
|
I need a method to render a Hit Dice rolling effect. For example, before the player hit the space bar, the dice will continuously rendering pic from 1 to 6.
My solution is to create a gif image that has that effect, and have the program load that gif image. Then when the player hit the space bar, the program will load another seperate image.
Do you have a better solution? How would you do it?
Thanks
|
|
|
|
|
Or you could have six different bitmap images, a timer set up, and for each WM_TIMER message received, display a different bitmap. Stop when the spacebar is pressed.
"Ideas are a dime a dozen. People who put them into action are priceless." - Unknown
|
|
|
|
|
I have vc6 installed. Can I install vc7 and not mess up the vc6 installation?
I need vc6 because some of my projects use some old 3rd party libs that just won't compile under vc7 and I can't really go into the code and fix the issues.
I'd like to use vc6 for those projects, and use vc7 for everything else.
Possible?
|
|
|
|
|
Yes. VC6, VS.NET 2002, and VS.NET 2003 will install and run side-by-side with no problems.
The only caution is, if you open a VC6 workspace/project in VS.NET, VS.NET will convert the workspace/project to a VS.NET solution/project file. If you need to go back to VC6, there isn't a reverse conversion (at least in the Microsoft provided tools).
A similar caution exists if you open a VS.NET 2002 solution/project in VS.NET 2003. In this case, VS.NET 2003 will convert the solution/project to the newer format in-place. Unless you kept a backup, the converted solution/project will not be loadable by VS.NET 2002.
Software Zen: delete this;
|
|
|
|
|
Along with what Gary said, I run three versions of VC without any problem - VC6, VC7 (VC++.NET) and embedded VC (for WinCE)
Cheers,
Tom Archer - Archer Consulting Group
"So look up ahead at times to come, despair is not for us. We have a world and more to see, while this remains behind." - James N. Rowe
|
|
|
|
|
Hi every body, how can i insert a bitmap in a combo box item, and show it?.
|
|
|
|
|
There are several articles in the combobox section that illustrate this. Here's just one from Mauricio Ritter that displays bitmaps in cbx items:
http://www.codeproject.com/combobox/multicombo.asp[^]
Cheers,
Tom Archer - Archer Consulting Group
"So look up ahead at times to come, despair is not for us. We have a world and more to see, while this remains behind." - James N. Rowe
|
|
|
|
|
|
How can I change the size of the 3 panes of the status bar?
(the one: m_wndStatusBar)
Thanks!
|
|
|
|
|
|
Can I cast BYTE* to char* , or BYTE* to CString and then back to BYTE ? What should I use for that ?
|
|
|
|
|
Lookup the CP author Mike Dunn. Then look at his String-articles (which he coauthored with Nishant). It should answer any questions you may have on strings.
--
An eye for an eye will only make the world blind.
|
|
|
|
|
BYTE == unsigned char. You can cast it.
You cannot cast BYTE* to CString, it's plainly not an instance of the CString class. CString s((char*)myBYTE*); should work tho.
Christian Graus - Microsoft MVP - C++
|
|
|
|
|
You cannot cast a BYTE* to char* or CString, but you can convert it to char* whit this method:
char* CAST(BYTE* bytes,int numberOfBytes)
{
char *result=new char[numberOfBytes];
for(int i=0;i
|
|
|
|
|
A BYTE is the same size as a char, hence you can cast a BYTE pointer to a char pointer.
You can even do the following:
<br />
DWORD d[4] = {0};<br />
char* p = (char* d );<br />
The code isn't going to be more nice with such casts, but you can still get away with it..
Blog[^]
|
|
|
|
|
I have the Id of a control for IDC_NUM1.
how to identify its type using the ID.
advance thanks if anybody let me know
Regards
Chezhian
|
|
|
|
|
Use GetDlgItem to get the window handle/object.
Use GetClassName to retrieve the class name.
 Pssst. You see that little light on your monitor? That's actually a government installed spy camera. Smile and wave to big brother!
|
|
|
|
|
Iam using MDI Doc-View architecture.
MY application displays customized controls (not derived from windows controls)on a tool bar.
I need to click on the of the control and drag and drop the control on the client area of the window.
When i drag the cursor should appropriately change to indicate drag operation.
I dont know it should be done in the LbuttonDown and Mouse Move event handlers.But I dont know the exact implementation.I need to know if any articles on this are available.
Please give me the URL.
Thanx in advance
laiju
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
