C / C++ / MFC

Rajesh R Subramanian14-May-09 23:11

Re: C++, simulations call center traffic [modified]

14-May-09 23:11

I usually try and ignore such pointless questions, but sometimes I just have to vent it out.

It is a crappy thing, but it's life -^ Carlo Pallini

CPallini14-May-09 23:28

CPallini

14-May-09 23:28

Don't worry, he has monkeys for that.
Big Grin | :-D

[added]
Sorry, I wasn't aware his monkeys were scheduled on another task [^]... Roll eyes | :rolleyes:

[/added]

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]

modified on Friday, May 15, 2009 7:56 AM

Rajesh R Subramanian14-May-09 23:33

14-May-09 23:33

On the other hand, he may not know what you're talking about. Smile | :)

It is a crappy thing, but it's life -^ Carlo Pallini

CPallini14-May-09 23:43

CPallini

14-May-09 23:43

Well monkeys are monkeys, after all. Moreover I suppose every developer should study Rajesh R Subramanian history... Roll eyes | :rolleyes:

Rajesh R Subramanian14-May-09 23:57

14-May-09 23:57

Well I may have a superb reason why you're completely wrong. Wink | ;)

It is a crappy thing, but it's life -^ Carlo Pallini

CPallini15-May-09 0:10

CPallini

15-May-09 0:10

OT: I suppose Iain being in Scandinavia now, it's a relatively long time since I have seen his last post here.
Smile | :)

Rajesh R Subramanian15-May-09 2:19

15-May-09 2:19

CPallini wrote:
Sorry, I wasn't aware his monkeys were scheduled on another task [^]... Roll eyes

You're crazy.

It is a crappy thing, but it's life -^ Carlo Pallini

Stuart Dootson15-May-09 0:01

DLL Import library missing

15-May-09 0:01

From your description, the way I'd do it would be to model each call as a period of time, chosen randomly using (probably) a normal distribution, where the mean and standard deviation are parameters to the simulation. A 5 minute mean and 3 or 4 minute standard deviation sound reasonable?

class Call
{
   Call(double currentTime) { // Generate random call duration, remember currentTime as the time we first saw the call }
   double CallMadeAt() const;
   double GetCallDuration() const;
};

std::stack<Call> callQueue;

You then have a fixed number of operators, each of which can handle one call at a time.

class Operator
{
   HandleCall(Call const& call, double currentTime) { // Remember that we're dealing with a call }
   bool Busy() const; // Flag to show we're handling a call currently
   double NextFreeTime() { return (pCall_)(pCall->GetCallDuration() + callStartTime_):(0.0); }
private:
   Call* pCall_;
   double callStartTime_;
};

Operator operators[OPERATOR_COUNT];

You can then model the passing of time, generating calls at random intervals (again using a normal distribution, but with different parameters) and passing them to free operators. If there's no free operator, you need to work out when the next operator's free and give them the call then.

Obviously, the hold time for a call is the time between the call being made and the call being handed off to an operator. You can measure the average hold time by summing them all and remembering how many there were.

HTH!

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

transoft14-May-09 12:57

14-May-09 12:57

Hi
I am using VC2005. I generated an empty DLL project. I addded all necessary files into project. I can compiled it. But I can not see the "Import Library".

What kind of reason will make the "Import Library" very big and DLL file small?

Best regards,

Stuart Dootson14-May-09 13:14

14-May-09 13:14

transoft wrote:
What kind of reason will make the "Import Library" very big and DLL file small?

? That doesn't go with But I can not see the "Import Library".

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

transoft14-May-09 16:26

14-May-09 16:26

Why I can not see the Import Library?

Thanks

Naveen14-May-09 17:55

Naveen

14-May-09 17:55

May be because you didnt export any thing....

nave

[OpenedFileFinder] [My Blog]

transoft15-May-09 1:43

15-May-09 1:43

Hi Dave

I did not find any place to set the export the library. Could you tell me where I can set?

Thanks

Naveen15-May-09 1:50

Naveen

15-May-09 1:50

transoft wrote:
Hi Dave

Did you mean Nave? Smile | :)

The lib file will be created automatically when you export a class or function from a dll. See the article Dlls are Simple. Part 1[^] if you want to know about exporting functions/class

nave

[OpenedFileFinder] [My Blog]

transoft15-May-09 1:52

15-May-09 1:52

Sorry Nave. That is my typo.

Thank you so much for answering my question.

transoft15-May-09 2:08

15-May-09 2:08

Hi Nave

Thank you for your guidance. I realized that I did not add "__declspec(dllexport)" these statement in my software. Actually I tried to build firebird database API into a DLL. I created a empty Win32 DLL using VS2005. It builds just fine. I can see a dll generated.

So I just need to add "__declspec(dllexport)" stuff to whatever I need, right?

Thanks

Naveen15-May-09 2:33

Naveen

15-May-09 2:33

Yes.. infront of all functions you wnat to export..

nave

[OpenedFileFinder] [My Blog]

Windows and Threads

BobInNJ14-May-09 11:17

BobInNJ

14-May-09 11:17

I have an application that creates several threads. One of these threads creates a (second) Window. When that thread goes away, the window it created goes away also. However, the pointer to the class that represents the window is still valid. It is never freed.

I would like the window to stay up when the thread that created it goes away. Is there a reasonable way to do this?

Bob

P.S. – I am under the impression that there is not.

bulg14-May-09 13:08

bulg

14-May-09 13:08

How'd you figure out that the pointer to the window was still valid?

BobInNJ14-May-09 13:20

BobInNJ

14-May-09 13:20

Thanks for the response. I claim that the pointer is still valid because it was allocated by doing a new and it was never freeded. It is my understanding that a pointer allocated in one thread, is valid in all threads. Is that wrong?

Bob

Stuart Dootson14-May-09 13:10

14-May-09 13:10

BobInNJ wrote:
I would like the window to stay up when the thread that created it goes away. Is there a reasonable way to do this?

No. The window requires its WndProc to be on the thread that created it. Each window's messages go via a message queue, which is a per-thread structure.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

BobInNJ14-May-09 13:22

BobInNJ

14-May-09 13:22

Thanks for the response.

Bob

Taran914-May-09 18:46

Taran9

14-May-09 18:46

Stuart,

Isn't message queue an application level data structure that's common to all its threads?

Stuart Dootson14-May-09 19:49

14-May-09 19:49

From this page[^]:

The system maintains a single system message queue and one thread-specific message queue for each graphical user interface (GUI) thread. To avoid the overhead of creating a message queue for nonGUI threads, all threads are created initially without a message queue. The system creates a thread-specific message queue only when the thread makes its first call to one of the User or Windows Graphics Device Interface (GDI) functions.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p