soft and program: comp.lang.c++ - 25 new messages in 6 topics

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* Motivation of software professionals - 9 messages, 8 authors
http://groups.google.com/group/comp.lang.c++/t/21a3fdec4dd53e6a?hl=en
* Loop generates never-ending sockets and threads, need help debugging - 6
messages, 5 authors
http://groups.google.com/group/comp.lang.c++/t/bfb43e94d5fe70d1?hl=en
* ❤～❤～❤ 2010 Cheap wholesale True Relig Jean, Laguna Beach Jean, G-star Jean,
Armani Jean ect at www.rijing-trade.com <Paypal Payment> - 1 messages, 1
author
http://groups.google.com/group/comp.lang.c++/t/78edc2eac9d4f289?hl=en
* dedektive , www detektei de , dedektiv , detektivbuero , werkschutz
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ueberwachung , + + + + +++ DETEKTEIEN DETEKTIVE ONLINE +++ DETEKTEI HAMBURG +++
PRIVATDETEKTIVE +++ + + http:// - 1 messages, 1 author
http://groups.google.com/group/comp.lang.c++/t/708c5972da0eb3b7?hl=en
* Incomplete types and std::vector - 3 messages, 3 authors
http://groups.google.com/group/comp.lang.c++/t/b0741c38fc15b5f7?hl=en
* Google AI Challenge at U of Waterloo - 5 messages, 5 authors
http://groups.google.com/group/comp.lang.c++/t/40f30c405afc24ab?hl=en

==============================================================================
TOPIC: Motivation of software professionals
http://groups.google.com/group/comp.lang.c++/t/21a3fdec4dd53e6a?hl=en
==============================================================================

== 1 of 9 ==
Date: Fri, Feb 5 2010 8:44 am
From: Tom Anderson

On Fri, 5 Feb 2010, Richard Cornford wrote:

> On Feb 5, 11:19 am, Stefan Kiryazov wrote:
>
>> I am doing a research about motivation in software development,
>> the most efficient practices to motivate software engineers,
>> their popularity, etc.
>
> Strange question; the most efficient motivator of professionals is
> money, and money is very popular.

There's a robust body of work that suggests this is very much *not* the
case. Money motivates some people; technical people are more motivated by
interesting work and respect from their colleagues.

tom

--
It is a formal cultural policy to show unreasonable bias towards any
woman who is both attractive and weird.

== 2 of 9 ==
Date: Fri, Feb 5 2010 9:00 am
From: ram@zedat.fu-berlin.de (Stefan Ram)

Stefan Kiryazov <stefan.kiryazov@gmail.com> writes:
>http://ask.wizefish.com/en/MotivationSurvey.aspx

This survey has a strong selection bias:

Real professionals are motivated by the money.

But those motivated by money will not attend
the survey as they are not being paid for it.

== 3 of 9 ==
Date: Fri, Feb 5 2010 9:54 am
From: Branimir Maksimovic

Stefan Kiryazov wrote:
> Hi all,
>
> I am doing a research about motivation in software development, the
> most efficient practices to motivate software engineers, their
> popularity, etc.

News server Im using doesn;t allow cross post without follow up header,
and max crosspost is three newsgroups.

Greets

== 4 of 9 ==
Date: Fri, Feb 5 2010 10:53 am
From: "Saga"

"Stefan Ram" <ram@zedat.fu-berlin.de> wrote in message
news:selection-20100205175941@ram.dialup.fu-berlin.de...
> Stefan Kiryazov <stefan.kiryazov@gmail.com> writes:
>>http://ask.wizefish.com/en/MotivationSurvey.aspx
>
> This survey has a strong selection bias:
>
> Real professionals are motivated by the money.
>
> But those motivated by money will not attend
> the survey as they are not being paid for it.

And those not motivated by money will also not
attend the survey because they'll think it is
offensive, catagorizing them as "non professional"
simply because they are not motivated by money.
Saga

== 5 of 9 ==
Date: Fri, Feb 5 2010 1:39 pm
From: Tom Anderson

On Fri, 5 Feb 2010, Patricia Shanahan wrote:

> That said, by definition professionals are, to some extent, in it for
> the money. If they were not, they would be amateurs as I am now.

Interesting. Do you think that all the non-financial rewards that are
available (if rarely!) in industry are available in academia or on
volunteer projects?

Something i find quite enjoyable, having moved from academia into
industry, is the sense that a project is actually doing something
valuable, something a business thinks is worth money. Work in academia and
the FOSS community can be very interesting, but a lot of it feels like
farting about.

tom

--
I sometimes think that the IETF is one of the crown jewels in all of
western civilization. -- Tim O'Reilly

== 6 of 9 ==
Date: Fri, Feb 5 2010 2:35 pm
From: Jedrin

If money was the only motivating factor wouldn't we all want to be
wall street bankers instead ?

== 7 of 9 ==
Date: Fri, Feb 5 2010 2:45 pm
From: Jorgen Grahn

On Fri, 2010-02-05, Stefan Kiryazov wrote:
> Hi all,
>
> I am doing a research about motivation in software development, the
> most efficient practices to motivate software engineers, their
> popularity, etc.
>
> As a part of the research, I am doing an online survey for software
> engineers and managers in software development. It takes just several
> minutes and filling it is a good opportunity to share your opinion
> about the motivation practices being used in the software industry
> today: [---]

I find it a bit odd that none of the questions had anything to do with
programming, or even technology or creative work in general. They
could have applied equally well to any kind of project-oriented work.

/Jorgen

--
// Jorgen Grahn <grahn@ Oo o. . .
\X/ snipabacken.se> O o .

== 8 of 9 ==
Date: Fri, Feb 5 2010 2:33 pm
From: yf110@vtn1.victoria.tc.ca (Malcolm Dew-Jones)

Jedrin (jrubiando@gmail.com) wrote:

: If money was the only motivating factor wouldn't we all want to be
: wall street bankers instead ?

Perhaps we all do - but until we get that chance...

== 9 of 9 ==
Date: Fri, Feb 5 2010 11:39 pm
From: Roedy Green

On Fri, 5 Feb 2010 04:23:41 -0800 (PST), Richard Cornford
<Richard@litotes.demon.co.uk> wrote, quoted or indirectly quoted
someone who said :

>
>Strange question; the most efficient motivator of professionals is
>money, and money is very popular.

That may be a motivator for taking a job, but I suspect is fairly far
down the list for leaving a job.

Leaving motivations might include:

personality conflict
boredom
too much pressure

Personally, the opportunity to do something I had never done before
was always the top priority. Employers usually want people who have
extensive specific experience.

In hiring, my main interest was loyalty. Employees don't get really
useful until after the first year. I don't expect them to hit the
ground running. I anticipate investing considerable effort in training
them. I looked for reasons why they would likely want to stay.
--
Roedy Green Canadian Mind Products
http://mindprod.com

You can't have great software without a great team, and most software teams behave like dysfunctional families.
~ Jim McCarthy

==============================================================================
TOPIC: Loop generates never-ending sockets and threads, need help debugging
http://groups.google.com/group/comp.lang.c++/t/bfb43e94d5fe70d1?hl=en
==============================================================================

== 1 of 6 ==
Date: Fri, Feb 5 2010 9:55 am
From: "Kurt"

Hi all,

I have a client/server project written by a hired contractor, but it's got a fairly big bug when it comes to dealing with thread and sockets. It creates threads but never closes the handle to them, thus causing the server to accumulate hundreds of thousands of open handles in a day or so. The client and server both share similar code, but I'll just post the server-side.

void CTransferServer::startCommandThread() {
int iCommandPort = _wtoi(configHandler->getTextValue(L"TransferCommandPort"));
SOCKET socCommand = CSocHandler::getServerSocket(iCommandPort);
if (socCommand == INVALID_SOCKET) {
//cout << "\nCould not create transfer command server socket." << WSAGetLastError();
return;
}

if (listen(socCommand, SOMAXCONN)) {
//cout << "\nCould not listen on transfer command port." << WSAGetLastError();
return;
}
while (blStarted) {
SOCKET sa = accept(socCommand, 0, 0); // block for connection request
if (sa ==INVALID_SOCKET) {
break;
}
void **params = (void **) malloc(sizeof(void*)*2);
SOCKET *s = new SOCKET;
*s = sa;
params[0] = (void*)this;
params[1] = (void*)s;
DWORD dwGenericThread;
//unsigned int iGenericThread;
HANDLE hWorkerThread = CreateThread(NULL, 0, transferCommandWorkerThread, params, 0, &dwGenericThread);
//HANDLE hWorkerThread = (HANDLE)_beginthreadex(NULL, 0, transferCommandWorkerThread, params, 0, &iGenericThread);
//WaitForSingleObject(hWorkerThread, INFINITE);
//CloseHandle(hWorkerThread);
}
}

DWORD WINAPI transferCommandWorkerThread(LPVOID param) {
void **params = (void **)param;
CTransferServer *transferServer = (CTransferServer*)params[0];
SOCKET *commandSocket = (SOCKET*)params[1];
transferServer->handleCommandConnection(*commandSocket);
delete commandSocket;
free((void*)params);
return 0;
}

So, the while-loop creates a socket that accepts a connection and passes it off to the thread. I am not 100% familiar with sockets and threads, but I have a general idea about them. As far as I can tell, the workerThread does close/delete the sockets properly, but the main loop never closes the handle to the thread. I tried adding WaitForSingleObject() and CloseHandle() but it appears to close the thread prematurely. This causes the communication between the server and client to get disconnected or in a deadlock state. I heard that _beginthreadex() is better to use, but when I tried that, I believe it made matters worse.

Any ideas on how to debug this or perhaps a better way of writing this?

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== 2 of 6 ==
Date: Fri, Feb 5 2010 11:10 am
From: Gert-Jan de Vos

On Feb 5, 6:55 pm, "Kurt" <n...@given.com> wrote:
> Hi all,
>
> I have a client/server project written by a hired contractor, but it's got a fairly big bug when it comes to dealing with thread and sockets. It creates threads but never closes the handle to them, thus causing the server to accumulate hundreds of thousands of open handles in a day or so. The client and server both share similar code, but I'll just post the server-side.
>
> void CTransferServer::startCommandThread() {
> int iCommandPort = _wtoi(configHandler->getTextValue(L"TransferCommandPort"));
> SOCKET socCommand = CSocHandler::getServerSocket(iCommandPort);
> if (socCommand == INVALID_SOCKET) {
> //cout << "\nCould not create transfer command server socket." << WSAGetLastError();
> return;
> }
>
> if (listen(socCommand, SOMAXCONN)) {
> //cout << "\nCould not listen on transfer command port." << WSAGetLastError();
> return;
> }
> while (blStarted) {
> SOCKET sa = accept(socCommand, 0, 0); // block for connection request
> if (sa ==INVALID_SOCKET) {
> break;
> }
> void **params = (void **) malloc(sizeof(void*)*2);
> SOCKET *s = new SOCKET;
> *s = sa;
> params[0] = (void*)this;
> params[1] = (void*)s;
> DWORD dwGenericThread;
> //unsigned int iGenericThread;
> HANDLE hWorkerThread = CreateThread(NULL, 0, transferCommandWorkerThread, params, 0, &dwGenericThread);
> //HANDLE hWorkerThread = (HANDLE)_beginthreadex(NULL, 0, transferCommandWorkerThread, params, 0, &iGenericThread);
> //WaitForSingleObject(hWorkerThread, INFINITE);
> //CloseHandle(hWorkerThread);
> }
>
> }
>
> DWORD WINAPI transferCommandWorkerThread(LPVOID param) {
> void **params = (void **)param;
> CTransferServer *transferServer = (CTransferServer*)params[0];
> SOCKET *commandSocket = (SOCKET*)params[1];
> transferServer->handleCommandConnection(*commandSocket);
> delete commandSocket;
> free((void*)params);
> return 0;
>
> }
>
> So, the while-loop creates a socket that accepts a connection and passes it off to the thread. I am not 100% familiar with sockets and threads, but I have a general idea about them. As far as I can tell, the workerThread does close/delete the sockets properly, but the main loop never closes the handle to the thread. I tried adding WaitForSingleObject() and CloseHandle() but it appears to close the thread prematurely. This causes the communication between the server and client to get disconnected or in a deadlock state. I heard that _beginthreadex() is better to use, but when I tried that, I believe it made matters worse.
>
> Any ideas on how to debug this or perhaps a better way of writing this?

Your analysis is correct. This is not very nice C++ code but your
problem can be fixed by using _beginthread() instead of
CreateThread(). This takes care of closing the thread handle at the
end of the thread.

== 3 of 6 ==
Date: Fri, Feb 5 2010 11:15 am
From: Branimir Maksimovic

Kurt wrote:
> Hi all,
>
> I have a client/server project written by a hired contractor, but it's got a fairly big bug when it comes to dealing with thread and sockets. It creates threads but never closes the handle to them, thus causing the server to accumulate hundreds of thousands of open handles in a day or so. The client and server both share similar code, but I'll just post the server-side.
>
....
> while (blStarted) {
> SOCKET sa = accept(socCommand, 0, 0); // block for connection request
> if (sa ==INVALID_SOCKET) {
> break;
> }
> void **params = (void **) malloc(sizeof(void*)*2);
> SOCKET *s = new SOCKET;
> *s = sa;
> params[0] = (void*)this;
> params[1] = (void*)s;
> DWORD dwGenericThread;
> //unsigned int iGenericThread;
> HANDLE hWorkerThread = CreateThread(NULL, 0, transferCommandWorkerThread, params, 0, &dwGenericThread);
> //HANDLE hWorkerThread = (HANDLE)_beginthreadex(NULL, 0, transferCommandWorkerThread, params, 0, &iGenericThread);
> //WaitForSingleObject(hWorkerThread, INFINITE);
> //CloseHandle(hWorkerThread);
> }
> }
>

Hm, what happens if there are more than 1 pending connection requests?
This obviously doesn't work in case of Wait.... since than, no other
connection will be accepted till current client is processed...

Greets

== 4 of 6 ==
Date: Fri, Feb 5 2010 12:39 pm
From: Kurt

On Feb 5, 2:15 pm, Branimir Maksimovic <bm...@hotmail.com> wrote:
> Kurt wrote:
> > Hi all,
>
> > I have a client/server project written by a hired contractor, but it's got a fairly big bug when it comes to dealing with thread and sockets. It creates threads but never closes the handle to them, thus causing the server to accumulate hundreds of thousands of open handles in a day or so. The client and server both share similar code, but I'll just post the server-side.
>
> ....
> > while (blStarted) {
> > SOCKET sa = accept(socCommand, 0, 0); // block for connection request
> > if (sa ==INVALID_SOCKET) {
> > break;
> > }
> > void **params = (void **) malloc(sizeof(void*)*2);
> > SOCKET *s = new SOCKET;
> > *s = sa;
> > params[0] = (void*)this;
> > params[1] = (void*)s;
> > DWORD dwGenericThread;
> > //unsigned int iGenericThread;
> > HANDLE hWorkerThread = CreateThread(NULL, 0, transferCommandWorkerThread, params, 0, &dwGenericThread);
> > //HANDLE hWorkerThread = (HANDLE)_beginthreadex(NULL, 0, transferCommandWorkerThread, params, 0, &iGenericThread);
> > //WaitForSingleObject(hWorkerThread, INFINITE);
> > //CloseHandle(hWorkerThread);
> > }
> > }
>
> Hm, what happens if there are more than 1 pending connection requests?
> This obviously doesn't work in case of Wait.... since than, no other
> connection will be accepted till current client is processed...
>
> Greets

I believe that may be the case as when I have one client transferring
data to the server, another client gets an error. I replaced the
clients with _beginthread() and am waiting for this current transfer
to finish, though I guess this would be a good opportunity to test out
the resume functionality. While on the subject of threads and sockets,
do you have any books to recommend?

Thanks,

Kurt

== 5 of 6 ==
Date: Fri, Feb 5 2010 12:57 pm
From: "Chris M. Thomasson"

"Kurt" <none@given.com> wrote in message
news:zYYan.3749$7S2.796@news.usenetserver.com...
> Hi all,
>
> I have a client/server project written by a hired contractor, but it's got
> a fairly big bug when it comes to dealing with thread and sockets. It
> creates threads but never closes the handle to them, thus causing the
> server to accumulate hundreds of thousands of open handles in a day or so.
> The client and server both share similar code, but I'll just post the
> server-side.

[...]

Have you tried just `CloseHandle()' right after the call to
`_beginthreadex()'? This would be equivalent to creating the thread in a
detached state. You don't need to wait for a detached thread to complete. If
that is not compatible, then you can call `CloseHandle()' right before you
return from the thread entry function. Also, FWIW, you only need
`_beginthreadex()' if the thread uses the CRT...

[...]

== 6 of 6 ==
Date: Fri, Feb 5 2010 1:27 pm
From: Kurt

On Feb 5, 3:57 pm, "Chris M. Thomasson" <n...@spam.invalid> wrote:
> "Kurt" <n...@given.com> wrote in message
>
> news:zYYan.3749$7S2.796@news.usenetserver.com...
>
> > Hi all,
>
> > I have a client/server project written by a hired contractor, but it's got
> > a fairly big bug when it comes to dealing with thread and sockets. It
> > creates threads but never closes the handle to them, thus causing the
> > server to accumulate hundreds of thousands of open handles in a day or so.
> > The client and server both share similar code, but I'll just post the
> > server-side.
>
> [...]
>
> Have you tried just `CloseHandle()' right after the call to
> `_beginthreadex()'? This would be equivalent to creating the thread in a
> detached state. You don't need to wait for a detached thread to complete. If
> that is not compatible, then you can call `CloseHandle()' right before you
> return from the thread entry function. Also, FWIW, you only need
> `_beginthreadex()' if the thread uses the CRT...
>
> [...]

I do not think the projects are using any CRT libraries, at least none
listed here: http://msdn.microsoft.com/en-us/library/abx4dbyh%28VS.80%29.aspx
I did not know that you could run CloseHandle() after creating the
thread, I assumed that it would cause it to stop. The reason I looked
into _beginthreadex() is because I read it was recommended over
CreateThread() due to some known memory leak. I have a few clients
running the beginthread() version, I'll see how it goes over the
weekend and if it doesn't close the threads properly, or causes
issues, I'll try CreateThread()/CloseHandle() in tandem.

Thanks.

==============================================================================
TOPIC: ❤～❤～❤ 2010 Cheap wholesale True Relig Jean, Laguna Beach Jean, G-star
Jean, Armani Jean ect at www.rijing-trade.com <Paypal Payment>
http://groups.google.com/group/comp.lang.c++/t/78edc2eac9d4f289?hl=en
==============================================================================

== 1 of 1 ==
Date: Fri, Feb 5 2010 10:14 am
From: "www.fjrjtrade.com"

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Jean, Armani Jean ect at www.rijing-trade.com <Paypal Payment>

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Friday, February 5, 2010

comp.lang.c++ - 25 new messages in 6 topics - digest

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