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baerten wrote: But it takes at the 100th loop 2seconds for one incrementation, thats very very slow LOL
Yes! When I tested it, I resumed after the breakpoint was hit (I set it to break at 2), looping
to 1000. after a few seconds I killed the process. It should have been done in way under a
second 
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Hi
We know that with prolog/epilog code bp is stored and we restore bp for every function call. Like this:
; Create a stack frame<br />
push ebp<br />
mov ebp,esp<br />
<br />
;codes here<br />
; Clean up the stack frame<br />
mov esp,ebp<br />
pop ebp
I read an interesting article. http://www.cprogramming.com/faq/cgi-bin/smartfaq.cgi?answer=1074726763&id=1073086407 It says:
Every time you call a function, a thingy (very technical term) called an activation record is pushed onto the stack. The activation record, also known as a stack frame, contains things such as local variables for the function, arguments, and the address of the previous activation record so that it knows how to return from whence it came. Because of these activation records, two calls to the same function aren't actually the same activation record, that's why recursion works. Each new call to fact_recursive has its own memory, its own argument copies, its own everything.
Because this all works like a stack, each new activation record covers up the previous record. When the function finally reaches the base case and returns, each activation record is popped from the stack until execution finally leaves the first call to fact_recursive. This is called unwinding the stack, you'll hear that term again sometime in your programming careers, but I won't say where.
We push bp so we can store it.
So If we optimize compiler that do not add prolog/epilog code, can't we use recursive functions? I said.
I tried with VC++ compiler by "Omittin frame pointer" /Oy . But recursive func. works. But i thought it mustnt work. I don't understand why it works. Where am i wrong?
Can you please explain reason of prolog/epilog code and whether there is a relation with prolog/epilog code with recursive func. call mechanism.
I am looking for your answers.
Thanks
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If FPO is enabled (via the /Oy option) it doesn't effect recursive functions. The return address is still stored on the stack; if it wasn't you couldn't even return from a function.
Steve
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Hi all,
I have generating a project like server-client communication using winsock. I would like to do that server application has keep connection to the database and retrieve some record set using CRecordset object from the database.
My questions are........
1) Can i write that CRecordset object into the file? after that can i read it from that file as a
CRecordset object? and send it to the client application.
2) If client application could retrieve the records from its retrieved CRecordset object?
If you know please tell me your suggestions and if you have any tutorials regarding to above the problem please lets me know
Thanks in Advance
regards
surezu
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what you're after is called serialization.
as you're using MFC, CRecordset already inherits from CObject, which provides a base for serialized object.
read more on the msdn about CObject::Serialize()
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<br />
1 void COBjSerializationDlg:: OnBnClickedDbw()<br />
2 {<br />
3 CString sIp,sDb,sPwd,sConn,sPort,sUn;<br />
4 sIp="192.168.2.17";<br />
5 sPort="5432";<br />
6 sPwd="fasp";<br />
7 try<br />
8 {<br />
9 sConn = "DRIVER={PostgreSQL ANSI};SERVER=" + sIp + ";port=" + sPort +<br />
";DATABASE=" + sPwd + ";UID=" + sPwd + ";PWD=" + sPwd + ";";<br />
10 db.OpenEx(sConn);<br />
11 }<br />
12 catch(CDBException *e)<br />
13 {<br />
14 MessageBox("Database Connection Refused."+e->m_strError,"DataBase<br />
15 Connection Error",MB_OK|MB_ICONERROR);<br />
16 e->Delete();<br />
17 }<br />
<br />
18 CRecordset rs(&db);<br />
<br />
19 rs.Open(AFX_DB_USE_DEFAULT_TYPE, "select name from master;");<br />
20 CFile file1;<br />
21 file1.Open("hexa.bin",CFile::modeCreate | CFile::modeWrite | CFile::typeBinary);<br />
22 CArchive ar1(&file1,CArchive:: store);<br />
23 if(ar1.IsStoring())<br />
24 {<br />
25 CObject:: Serialize(ar1);<br />
26 ar1 << &rs;<br />
27 }<br />
28 ar1.Flush();<br />
29 ar1.Close();<br />
30 file1.Close();<br />
31 rs.Close();<br />
32 db.Close();<br />
33 }<br />
<br />
<br />
<br />
34 void COBjSerializationDlg:: OnBnClickedDbr()<br />
35 {<br />
36 CRecordset *set = new CRecordset();<br />
37 CFile file2;<br />
38 file2.Open("hexa.bin", CFile::modeRead| CFile::typeBinary);<br />
39 CArchive ar2(&file2,CArchive:: load);<br />
40 if(ar2.IsLoading())<br />
41 {<br />
42 CObject:: Serialize(ar2);<br />
43 ar2 >> set;<br />
44 }<br />
45 set.MoveFirst();<br />
46 int j;<br />
47 j = 0;<br />
48 CString s;<br />
49 while(set.IsEOF())<br />
50 {<br />
51 s = "";<br />
52 set.GetFieldValue (j,s);<br />
53 AfxMessageBox(s);<br />
54 set.MoveNext();<br />
55 }<br />
56 ar2.Flush();<br />
57 ar2.Close();<br />
58 set.Close();<br />
59 file2.Close();<br />
60 delete set;<br />
61 }
error C2679: binary '>>' : no operator found which takes a right-hand operand of type 'CRecordset *__w64 ' (or there is no acceptable conversion)
will be thrown during the compilation of the above code at LINE.NO:43
please help me.....what i did wrong in my snippet....
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Regarding question 1 - You might want to try deriving from CRecordset, implementing a Serialize() function and saving your objects in a CArchive ...
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1 void COBjSerializationDlg:: OnBnClickedDbw()<br />
2 {<br />
3 CString sIp,sDb,sPwd,sConn,sPort,sUn;<br />
4 sIp="192.168.2.17";<br />
5 sPort="5432";<br />
6 sPwd="fasp";<br />
7 try<br />
8 {<br />
9 sConn = "DRIVER={PostgreSQL ANSI};SERVER=" + sIp + ";port=" + sPort +<br />
";DATABASE=" + sPwd + ";UID=" + sPwd + ";PWD=" + sPwd + ";";<br />
10 db.OpenEx(sConn);<br />
11 }<br />
12 catch(CDBException *e)<br />
13 {<br />
14 MessageBox("Database Connection Refused."+e->m_strError,"DataBase<br />
15 Connection Error",MB_OK|MB_ICONERROR);<br />
16 e->Delete();<br />
17 }<br />
<br />
18 CRecordset rs(&db);<br />
<br />
19 rs.Open(AFX_DB_USE_DEFAULT_TYPE, "select name from master;");<br />
20 CFile file1;<br />
21 file1.Open("hexa.bin",CFile::modeCreate | CFile::modeWrite | CFile::typeBinary);<br />
22 CArchive ar1(&file1,CArchive:: store);<br />
23 if(ar1.IsStoring())<br />
24 {<br />
25 CObject:: Serialize(ar1);<br />
26 ar1 << &rs;<br />
27 }<br />
28 ar1.Flush();<br />
29 ar1.Close();<br />
30 file1.Close();<br />
31 rs.Close();<br />
32 db.Close();<br />
33 }<br />
<br />
<br />
<br />
34 void COBjSerializationDlg:: OnBnClickedDbr()<br />
35 {<br />
36 CRecordset *set = new CRecordset();<br />
37 CFile file2;<br />
38 file2.Open("hexa.bin", CFile::modeRead| CFile::typeBinary);<br />
39 CArchive ar2(&file2,CArchive:: load);<br />
40 if(ar2.IsLoading())<br />
41 {<br />
42 CObject:: Serialize(ar2);<br />
43 ar2 >> set;<br />
44 }<br />
45 set.MoveFirst();<br />
46 int j;<br />
47 j = 0;<br />
48 CString s;<br />
49 while(set.IsEOF())<br />
50 {<br />
51 s = "";<br />
52 set.GetFieldValue (j,s);<br />
53 AfxMessageBox(s);<br />
54 set.MoveNext();<br />
55 }<br />
56 ar2.Flush();<br />
57 ar2.Close();<br />
58 set.Close();<br />
59 file2.Close();<br />
60 delete set;<br />
61 }
error C2679: binary '>>' : no operator found which takes a right-hand operand of type 'CRecordset *__w64 ' (or there is no acceptable conversion)
will be thrown during the compilation of the above code at LINE.NO:43
please help me.....what i did wrong in my snippet....
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I think you should derive from CRecordset, and in the derived class implement the Serialize function where you will save/load the relevant data to/from the object. Then call your Serialize function directly - set.Serialize(ar).
That should do the trick ...
Hope this help.
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It's much easier to make a class that represents a record and make that class serializable.
A CRecordset "represents a set of records selected from a data source". You can
probably come up with a way to serialize it but it will be complicated. To unserialize you
need to have the recordset ready to insert records...It can be done but it makes no sense on
the client end in a client/server situation.
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Thank you for your suggestions.......
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Hello all,
Which files should I copy into the other computer in order to be able to use an app made with VC++2005 in a computer without the development tools installed?
Thank you in advance.
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You can download an exe file called vcredist_x86.exe from microsoft. This EXE copies all of the required MFC and VC DLLs to the proper locations ...
Just run the EXE as part of your setup.
If you have trouble find the EXE, let me know I'll email it to you ...
Hope this helps.
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Great, it seems I need the MSI3.1, but I've just downloaded it and now it is installing.
Thank you.
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I've done that, installed the MSI3.1, and then the vcredist, and after all the app continues without running.
Any idea? thank you in advance.
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What is the error message you are receiving ?
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You was not able to start the application because the configuration is not correct. Reinstall the application can solve the problem.
I've copied the exe directly and nothing else...
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Oh, sorry, I probably didn't explain myself properly ...
You need to run the vcredist_x86.exe on the target PC (the one without the VC2005) so that it deploys the VC & MFC DLLs, and only then run your application.
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Yes, this is what I've done... the strangest thing is that at the end the VCREDIST don't show any message...
and at the end, when I try to execute the programa the problem appears...
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Is your app built in debug or release ?
If it's in Debug, then that's the problem ... the vcredist_x86.exe only deploys the release version of the required DLLs ... if your application is built in debug then it's dependant upon the debug versions of MFC/VC and they are probably missing. Try to deploy a release version of your app.
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I've also tried that... 
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Maybe you have a lib that's compiled in debug in your application ? 
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No, I've even made a new solution, and tried to compile it in release mode. After doing that, the same result...
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Hi,
Once I got it right to run an application, developed in VS2005 VC++ without having to run any external application, before hand. I linked statically to a couple of lib's. I cant remeber their names, but it worked.
Have a look at: C Run-Time Libraries (CRT)[^]
Regards,
The only programmers that are better than C programmers are those who code in 1's and 0's..... 
Programm3r
My Blog: ^_^
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The best way is to create a setup project to install it, or run the .exe the others have told you about. There is a quick and dirty way that works on XP, you can just copy the .dll's that you want but you have to put them into directories with their manifests. For example, (from here[^])
to include Microsoft.VC80.MFC.dll you need to copy the \Microsoft.VC80.MFC directory from %VCINSTALLDIR%\redist\ into the loacl application directory like:
<br />
\bin\<br />
myApplication.exe<br />
\Microsoft.VC80.MFC<br />
This works on XP but I don't think it works on earlier OSs. Of course, ensure you have the release build, otherwise you would need the debug dlls.
Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."
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