Thread synchronization - C / C++ / MFC Discussion Boards

santhoshv842-Oct-08 22:32

2-Oct-08 22:32

Hi,

There you have just specified two folders name.
What happened to the file name.
Because its SHFileOperation file operation..

Re: UnWanted Error Show

Michael Schubert2-Oct-08 23:01

Michael Schubert

2-Oct-08 23:01

TeVc++ wrote:
urgent

For urgentz matterz plz askz CPallini. He willz helpz.

Re: UnWanted Error Show

Hamid_RT2-Oct-08 23:28

Hamid_RT

2-Oct-08 23:28

TeVc++ wrote:
Plz help me it's urgent sir..

Of course when you use of this phrase you must be wait for CPallini but
your code is working for me:

SHFILEOPSTRUCT p={0};
p.wFunc = FO_COPY;
p.pTo   = _T("c:\\");
p.pFrom = _T("c:\\2\\1");

SHFileOperation(&p);

You got this error because you use of p.pFrom = _T("c:\\2\\"); but you must be set a name after \\

Re: UnWanted Error Show

Michael Schubert2-Oct-08 23:10

Michael Schubert

2-Oct-08 23:10

Did you try to use flags for SHFILEOPSTRUCT, like FOF_MULTIDESTFILES ? Did you read the documentation?

Re: UnWanted Error Show [modified]

Rajesh R Subramanian2-Oct-08 23:30

Rajesh R Subramanian

2-Oct-08 23:30

Try this:

LPCTSTR lpFrom = _T("D:\\SymbianDev\\Test\0");
LPCTSTR lpTo = _T("D:\\SymbianDev\\Test1\0");

SHFILEOPSTRUCT fos ={0};
fos.wFunc = FO_COPY;
fos.pTo   = lpTo;
fos.pFrom = lpFrom;

if(::SHFileOperation(&fos) == 0)
    cout<<"SHFileOperation succeeded"<<endl;

Many are stubborn in pursuit of the path they have chosen, few in pursuit of the goal - Friedrich Nietzsche

.·´¯`·->Rajesh<-·´¯`·.
[Microsoft MVP - Visual C++]

modified on Friday, October 3, 2008 6:42 AM

Re: UnWanted Error Show

SandipG 3-Oct-08 0:33

SandipG

3-Oct-08 0:33

One suggestion

Rajesh R Subramanian wrote:
LPCTSTR lpFrom = _T("D:\\SymbianDev\\Test");
LPCTSTR lpTo = _T("D:\\SymbianDev\\Test1");

should end with two null characters
At least document says that i don't know if it works without that Smile | :)

Regards,
Sandip.

Re: UnWanted Error Show

Rajesh R Subramanian3-Oct-08 0:43

Rajesh R Subramanian

3-Oct-08 0:43

Luckily, it works. But that's a good point there. I will modify my previous post.

Many are stubborn in pursuit of the path they have chosen, few in pursuit of the goal - Friedrich Nietzsche

.·´¯`·->Rajesh<-·´¯`·.
[Microsoft MVP - Visual C++]

Thread synchronization

singh_nav2-Oct-08 19:05

singh_nav

2-Oct-08 19:05

Hi all,

I am having a list(queue)of tasks. My two threads are using the same list.

First thread is to insert the task into it. (appending the list)
Second thread is to process on each task . ( reading the list)

My aim is to give the maximum availability to Thread one without hanging thread two.

How to synchronize both thread so that, second thread should not wait for long and First thread keep inserting the item into list.

Thanks in advance

Re: Thread synchronization

ThatsAlok2-Oct-08 19:36

ThatsAlok

2-Oct-08 19:36

critical section! look for CCriticalSection class in MFC!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
Never mind - my own stupidity is the source of every "problem" - Mixture

cheers,
Alok Gupta
VC Forum Q&A :- I/IV
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Re: Thread synchronization

Roger Stoltz2-Oct-08 22:14

Roger Stoltz

2-Oct-08 22:14

A piece of good advice is to stay clear of the MFC synchronization objects because they are not working properly. They may fail under certain circumstances.
E.g. you cannot recursively lock a CCriticalSection from the same thread because it will cause a deadlock.
Use the Win32 API with ::EnterCriticalSection() and ::LeaveCriticalSection() instead.

Read more here[^].

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown

Re: Thread synchronization

Cedric Moonen3-Oct-08 1:18

Cedric Moonen

3-Oct-08 1:18

Roger Stoltz wrote:
E.g. you cannot recursively lock a CCriticalSection from the same thread because it will cause a deadlock.

Wow, thanks for the info Roger. I've never used the MFC sync objects before but I don't think I will ever use them now.

Cédric Moonen
Software developer

Charting control [v1.5]
OpenGL game tutorial in C++

Re: Thread synchronization

Roger Stoltz3-Oct-08 1:28

Roger Stoltz

3-Oct-08 1:28

Yup, pretty amazing, isn't it?

But the evidence is right there in the code. Dead | X|

I've never used the MFC sync classes since I read Joe's advice many years ago in a much earlier essay of his.

Even though CCriticalSection may work if it's only locked once in a call chain, you will eventually find yourself in a situation where you should perform a second lock due to encapsulation and at that time you're smoked; a re-write using the Win32 primitives is essential before it has a chance of working.

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown

If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

Greg Ellis2-Oct-08 15:11

Greg Ellis

2-Oct-08 15:11

Hey Guys,

I have always used MFC, but now that I have upgraded to visual studio 2005 and 2008 I am forced to use MSI installers due to the depencies on the new merge modules. I really don't like the msi installer I think it's horrible and I would rather use inno setup or the old wise installer.

I just want to be sure.... If I was to start writing all my code in a pure Win32 Application from vs 2005 or 2008 I would no longer require the vcredist files in order to run my applications correct?

Thanks,
Greg

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

Saurabh.Garg2-Oct-08 15:52

Saurabh.Garg

2-Oct-08 15:52

Your application will still depend on CRT DLL's.

You don't necessarily have to use MSI or other installers. You can always deploy you application using private assemblies. Read this article http://www.codeproject.com/KB/cpp/vcredists_x86.aspx[^], for more details. There is a section on "Install a private assembly".

-Saurabh

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

Greg Ellis2-Oct-08 17:48

Greg Ellis

2-Oct-08 17:48

Thank you very much! Smile | :)

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

Saurabh.Garg2-Oct-08 18:32

Saurabh.Garg

2-Oct-08 18:32

You are welcome.

-Saurabh

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

CPallini2-Oct-08 21:21

CPallini

2-Oct-08 21:21

You may also link with static CRT library.
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]

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

Saurabh.Garg2-Oct-08 21:34

Saurabh.Garg

2-Oct-08 21:34

I generally don't advise doing that since in long run it might create very obscure bugs. If you link application with static CRT and later on use a library which was linked dynamically with CRT then it might create all sorts of problems from multiple defined symbols during linking to incorrect handling of resources.

-Saurabh

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

CPallini2-Oct-08 21:41

CPallini

2-Oct-08 21:41

Saurabh.Garg wrote:
If you link application with static CRT and later on use a library which was linked dynamically with CRT then it might create all sorts of problems from multiple defined symbols during linking to incorrect handling of resources.

Well, the above is not, IMHO, an obscure bug.

Statically linking the CRT ramain a valid option, IMHO.
Smile | :)

Re: If I build a Win32 Application in vs 2005 or 2008 it has no dependencies correct?

Saurabh.Garg2-Oct-08 22:44

Saurabh.Garg

2-Oct-08 22:44

Linking with static CRT is definitely a valid option. I call such bugs obscure because sometimes a 3rd party library can be added long after choosing to link with static CRT and suddenly a working application might start crashing.

-Saurabh

How to insert a toolbar into a ordinary dialog box?

Joseph Marzbani2-Oct-08 12:14

Joseph Marzbani

2-Oct-08 12:14

I guess that's an old (or maybe funny for you masters Laugh | :laugh: