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In general you just call it. Be warned however; multithreading introduces many new and often unexpected complexities to an application. If you don't understand these complexities you're better off avoiding it. For example something as simple as incrementing a variable might not work as expected if more then one thread tries to "touch" it at the same time. If you've never heard of EnterCriticalSection, LeaveCriticalSection, InterlockedIncrement and many others, don't even consider using multiple threads.
Steve
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Thanks but I already tried that and unfortunately it did not work. It had an error saying that the function is an external function or something.
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This doesn't sound like a threading problem to me. Can you call the function at all even when no threading is used (in the same file as you do when threading is used)?
Steve
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yes I can. I've been looking at every possible problem but it seems like the thread is it. the thread can't see the function i declared in the main class.
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Llasus wrote: the thread can't see the function i declared in the main class.
The compiler knows nothing about threads. Threads are supported by the OS and the C-runtime library so the visibility of functions will not be effected. That's why I suggested putting the call to the function in the same file (and as close as possible) as the call made in the thread function: as location is an issue.
Steve
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I tried putting the function in the same file as the thread and it still generated the same error as it cant see the function when called in the thread.
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Perhaps if you posted some code and the exact error message text something might reveal itself.
Steve
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Ok here are cutout of the codes that i have..
in LPAServerDlg.h
class CLPAServerDlg : public CDialog<br />
{<br />
public:<br />
void AddListItem(CString strbufffn, CString strbuffip,<br />
CString strbuffdate, CString strbuffstat);<br />
}
in LPAServerDlg.cpp
DWORD WINAPI ListenThread(LPVOID lParam);<br />
DWORD WINAPI ReceiveThread(LPVOID lParam);
<br />
class CAboutDlg : public CDialog<br />
{<br />
};<br />
<br />
CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)<br />
{<br />
}<br />
<br />
DWORD WINAPI ReceiveThread(LPVOID lParam)<br />
{<br />
...codes<br />
AddListItem(strbufffn, strbuffipa, "Time", "Printing");<br />
...codes<br />
}<br />
<br />
DWORD WINAPI ListenThread(LPVOID lParam)<br />
{<br />
..codes<br />
hThread = CreateThread(0, 0, ReceiveThread, (LPVOID)Message, 0, NULL);<br />
..codes<br />
}<br />
<br />
void CLPAServerDlg::AddListItem(CString strbufffn, CString strbuffip,<br />
CString strbuffdate, CString strbuffstat)<br />
{<br />
int nItem;<br />
<br />
nItem = m_ListFile.InsertItem(0,strbufffn);<br />
m_ListFile.SetItemText(nItem, 1,strbuffip);<br />
m_ListFile.SetItemText(nItem, 2,strbuffdate);<br />
m_ListFile.SetItemText(nItem, 3,strbuffstat);<br />
}<br />
error C2440: '=' : from 'void (__thiscall CLPAServerDlg::*)(class CString,class CString,class CString,class CString)' to 'void (__cdecl *)(class CString,class CString
,class CString,class CString)' cannot change. (see the new of operation ; help)
sorry bout the error message.. its all in japanese and i just translated it. Thanks again for all your time and help!
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Can you indicate on which line the error occurs?
Steve
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oh, sorry but i pasted the wrong error message. the error line there occured on the call of the AddLIstItem() on the ReceiveThread.
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I'm still not sure where the error occured or now if the error you gave is the correct error. If the error message is correct it means you're trying to assign a member function pointer to a pointer that expects a "free" (non member) function.
Steve
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I made changes in my code earlier thats why i pasted the wrong error message. I attempted earlier to pass the function's address to the thread but failed. Still i cant directly call a function of the class inside a thread even though they are of the same file.
Here is the correct error message..
E:\Program Files\Microsoft Visual Studio\MyProjects\LPAServer\LPAServerDlg.cpp(355) : error C2065: 'AddListItem' : It is the discernment child who is not defined.
Again, thanks alot for the time Steve
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I haven't got the whole file so line numbers don't tell me where the error occured. You'll have to show post some code and mark the line where the error occurs.
Steve
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DWORD WINAPI ReceiveThread(LPVOID lParam)<br />
{<br />
...codes<br />
AddListItem(strbufffn, strbuffipa, "Time", "Printing");
...codes<br />
}
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ReceiveThread is a global function not a class member. AddListItem is a member function. You have to call a member function either in another member function or qualify the call using a . or a ->.
Steve
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You need an object of your class type to call a non-static member function of that type.
You could pass an object (pointer) into your thread proc via the lParam:
DWORD WINAPI ReceiveThread(LPVOID lParam)
{
MyClass *pMyClass = (MyClass *)lParam;
//some processing here
pMyClass->AddListItem(...);
}
Pass the MyClass pointer as the LPVOID lpParameter in the CreateThread() call.
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ok ill try that in a bit. but would it also be possible of passing the pointer of the function?
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Llasus wrote: but would it also be possible of passing the pointer of the function?
Yes, but only if it's a static method, or a regular function.
--
Featuring GRATUITOUS ALIEN NUDITY
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i have tried doing a static method however, since inside the function i am doing access to a non-static CListCtrl in which ill need to add items to it generates the error that it cant recognize the CListCtrl of the list in the dialog box.
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Thanks Mark, I have already solved the problem using your way by passing the pointer to the class. 
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In icon view... is there a way to set the spacing between the top border and the top items? I'm using set position, but when I scroll down and then up again, the top icons are reassigned to a distance of about 2 pixels from the border.
This is how it looks:
-----------------------
| TTTT | 1 or 2 pixels (default)
| |
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This is what i want:
-----------------------
| | 20 pixels
| TTTT |
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Have you played around with the LVS_ALIGNxxx styles?
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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You mean LVS_ALIGNTOP and LVS_ALIGNLEFT? There's nothing I can play with there...
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skullfire wrote: You mean LVS_ALIGNTOP and LVS_ALIGNLEFT?
Yes, and LVS_ALIGNRIGHT and LVS_ALIGNBOTTOM.
skullfire wrote: There's nothing I can play with there...
Why not?
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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Hi,
I wonder if unsigned 64bit integer is valid on a vc++ 6.0 compiler. In my application I have to use uint64 data type and whenever I try to use the command that is assigned to this, it fails. These are the two syntaxes that I have to use to define the buffers and the second one is for 64bit unsigned integer buffer on a system having a 64bit compiler and the first one is for systems with non-64bit compiler. If I have to use the first one, how can I define the low/high offsets and low/high transferlen.
Suppose I want to start the buffer with zero offset and buffer length of 1024x1024bytes.
//*************************************************************************
uint32 _stdcall spcm_dwDefTransfer_i64m(// Defines the transer buffer by using 2 x 32 bit unsigned integer values for each 64 bit value
drv_handle hDevice, // handle to an already opened device
uint32 dwBufType, // type of the buffer to define
uint32 dwDirection, // the transfer direction as defined above
uint32 dwNotifySize, // amount of bytes after which i want do receive
void* pvDataBuffer, // pointer to the data buffer
uint32 dwBrdOffsH, // high part of offset in board memory
uint32 dwBrdOffsL, // low part of offset in board memory
uint32 dwTransferLenH, // high part of transfer buffer length
uint32 dwTransferLenL); // low part of transfer buffer length
//*************************************************************************
uint32 _stdcall spcm_dwDefTransfer_i64 (// Defines the transer buffer by using 64 bit unsigned integer values
drv_handle hDevice, // handle to an already opened device
uint32 dwBufType, // type of the buffer to define as listed above
uint32 dwDirection, // the transfer direction as defined above
uint32 dwNotifySize, // amount of bytes after which i want do receive
void* pvDataBuffer, // pointer to the data buffer
uint64 qwBrdOffs, // offset for transfer in board memory
uint64 qwTransferLen); // buffer length
thanks,
-Pavan.
-- modified at 18:07 Wednesday 8th November, 2006
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