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It's not an API, it's a function that someone wrote. The code is provided in the post[^].
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I am not 100% sure how keyboard input works, so I thought I'd ask it here.
I already asked about blocking joystick devices in C++, but I got no answers 
See here: http://www.codeproject.com/script/comments/forums.asp?msg=2038033&forumid=1647&mode=all&userid=4049045#xx2038033xx
[^]
Mostly, I am curious if there is a way to detect keyboard input from a "real keyboard" and differentiate it from a clicker/macro program. I want to do this in C++. I know there are WinAPI functions as well as Direct3d functions for such things, but I couldn't find any information on if it's possible to tell them apart.
Any answers would be appreciated. Thanks in advance.
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You can use SetWindowsHookEx() with the WH_KEYBOARD_LL parameter to monitor all low-level keyboard messages. From the callback function, LowLevelKeyboardProc(), you can block any of the messages by returning a nonzero value, so that the message isn't sent to the target window. You could do something like this:
...
//Prototypes
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK LowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam);
...
//Global variables
HHOOK hLowlevelKeyboardHook; //Low-level keyboard hook handle
...
//Main Window Callback function
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
...
switch(msg)
{
case WM_CREATE:
hLowlevelKeyboardHook=SetWindowsHookEx(WH_KEYBOARD_LL, //Low-level keyboard messages
LowLevelKeyboardProc, //Hook Callback function
NULL, //Monitor all system messages
0 //Monitor all system messages
);
break;
}
...
}
...
LRESULT CALLBACK LowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam)
{
LPKBDLLHOOKSTRUCT kbdst;
if(nCode<0) //No message to process
return CallNextHookEx(hLowlevelKeyboardHook, nCode, wParam, lParam);
//Block all keyboard messages, if they are the letter 'A'
kbdst=(LPKBDLLHOOKSTRUCT)lParam;
if(kbdst->vkCode==41)
return -1;
//Otherwise, send the message to the next hook
return CallNextHookEx(hLowlevelKeyboardHook, nCode, wParam, lParam);
}
Hope this helps!
--PerspX
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I have a requirement to read data from a serial port and send it out over a network port. The data must be sent when either of these two conditions are met:
1) 1400 bytes read.
2) 20 milliseconds have elapsed since the last read finished (if no data is present wait another 20 ms or until condition 1)
To try an meet these goals I am using overlapped IO. Here is the read:
ReadFile(hComm, ReadBuffer, 1400, &dwRead, &osReader);
I am trying to use a Waitable Timer to signal the 20 ms for requirement 2. The problem is how do I stop the current read operation and get all the characters that have been read when the timer expires? I tried using WaitForMultipleObjects but I am stuck on what to do when the timer expires.
I am writing this application in VC++ using Visual Studio 2005, target platform is Windows XP.
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RMLPilot wrote: The problem is how do I stop the current read operation
Have you looked at SetCommTimeouts()?
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Hans Dietrich wrote: Have you looked at SetCommTimeouts()?
I tried a look at SetCommTimeouts() but it did not work. Perhaps I had the parameters wrong. I used the following:
COMMTIMEOUTS Timeouts;
ZeroMemory(&Timeouts, sizeof(COMMTIMEOUTS));
Timeouts.ReadIntervalTimeout = 20;
Timeouts.ReadTotalTimeoutMultiplier = 0;
Timeouts.ReadTotalTimeoutConstant = 20;
Timeouts.WriteTotalTimeoutMultiplier = 0;
Timeouts.WriteTotalTimeoutConstant = 0;
SetCommTimeouts(Timeouts);
My understanding of these values is the I shouldn't get the event unless either 20 ms has passed between input bytes or (0 ms * 1400 bytes) + 20 ms has passed. This did not seem to work, I got about a second delay between events. Did I misinterpret the documentation on this call?
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How about using async I/O, aka overlapped I/O, to talk to the serial port and, then if your timer expires, cancel the ReadFile using the CancelIo.
One thing to consider is if a partial block of data comes in when your timer expires. What will you do if 500 bytes have come in when your timer expires?
Assuming the source of the data always puts the data onto the serial line in 1400 byte chunks, another idea to consider is to not use a continuous retry loop to read the data. Instead, use the WaitCommEvent function to detect when a byte has been read by the port and then calling the ReadFile to read the 1400 bytes.
Judy
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 i have been mad on my code it give me results i cant fingure out how they come
i want to find how many words there are in a string
yes123ok2 no but !@#$ ok <=== 5 words
my code
int CInfoRecoverDlg::WordDocu(CString line)
{
int y= 0;
int x = line.GetLength();
for ( int i = 0 ; i < x ; i++)
{
if ( x >1)
{
if ( !_istalpha((line.GetAt(i)) && _istalpha(line.GetAt(i-1))))
{
y = y +1;
}
}
}
return y;
}
void CInfoRecoverDlg::OnButton1()
{
CString str1;
CString str = "yes";
CString line = "2d1s";
CString str2;
str2.Format(_T("%d"),WordDocu(line));
AfxMessageBox(str2);
}
i dont care so much to correct the code but for how much stupid f***ing retard i could be
the AfxMessageBox appear me 4 while
i try to say with my code if index = not character and (index-1) = character then there will be 1 word
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I guess first of all, how do you define a word?
What separates words? Any non alphabetic character including whitespace?
Just whitespace?
How many words are in this string - "yes123ok2"
How many do you expect in this string "!@#$ ok" ?
I thought I read in other post that you're looking for words like google search line.
If so, looking for whitespace seems the way to go.
So a string like "yes no maybe" is 3 words.
Is that what you are trying to do?
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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i am trying to do yes123ok2 = 2 words 
!@#$ok = 1 word !!@#$ ok = 1 word
yes no maybe = 3 words
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Also
Hello !My name is Papas, John Papas!
i want to take as words My Papas and Papas too (not only the words between whitespace)
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well the code work fine (once again) but only for the CString i intiallize and valued inside my code
when i try to read a file.txt
file.txt :
yes ok i will say "yes"
and i want to compare with CString str = "yes"; it doesn't work find
but if i want to compare CString str1 = "yes ok i will say \"yes\"" with CString st2 = "yes" then it work fine :/
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Immunity18 wrote: well the code work fine (once again) but only for the CString i intiallize and valued inside my code
In that case, don't touch anything!  Look at the string you read from the file in the debugger.
What's different about it?
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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I think you want if(i>1) not if(x>1) in the for loop. (Or just start the loop with i=1 since you don't do anything in the i=0 iteration.)
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After I split the main frame into 2 row x 1 column. Standard AfxMessageBox no longer displaying and hang the program in MFC. What is the problem?
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How did you split the window?
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
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I have a SDI application in MFC. I split the main frame to 2 rows and 1 columm, then further split first row of the main frame to 1 row and 2 columns statically. the following code is added to OnCreateClient().
// split main frame
m_mainSplitterFrame.CreateStatic(this,2,1);
// further split top main frame to one row and 2 columns
m_childSplitterFrame.CreateStatic(&m_mainSplitterFrame,2,1, WS_CHILD | WS_VISISBLE,m_mainSpitterFrame.IdFromColRow(0,0));
//Create view for sub frame
m_childSplitterFrame.CreateView(0,0,RUNTIME_CLASS(CMyChildView),CSize(100,100),pContext);
m_childSplitterFrame.CreateView(0,1,RUNTIME_CLASS(CMyChildView),CSize(100,100),pContext);
// create bottom view
m_mainSplitterFrame.createView(1,0,RUNTIME_CLASS(CMyMainView),CSize(100,100),pcontext);
retrun TRUE;
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Well, Im not sure about... It can be an intern conflict with the frames/windows. Does the MessageBox (NULL, "Message", "Caption", MB_OK); work?
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
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i got this warning when i try to use isletter() in my WordDocu()
{
CString p[26];
CString v[26];
p[0] = "A";
p[1] = "B";
......
p[24] = "Y";
p[25] = "Z";
v[0] = "a";
v[1] = "b";
....
v[24] = "y";
v[25] = "z";
for (int i = 0 ; i <26 ; i++)
{
if ( v[i] == str || p[i] == str)
{
return FALSE;
break;
}
else if ( i==25 &&( v[i] != str && p[i] != str))
{
return TRUE;
}
else
{
return TRUE;
}
}
}
is there any path i dont wrote return TRUE/FALSE ? :/
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It doesn't look like it.
Maybe you fooled the compiler by putting a break; after a return.
And why have a for() loop if it always exits the first iteration?
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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i want to know when a GetAt(i) is not letter (a-z A-Z) so it would be 1234567890!@$#^%^ etc
i want this so i can find how many words exist in a string
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Immunity18 wrote: want to know when a GetAt(i) is not letter (a-z A-Z) so it would be 1234567890!@$#^%^ etc
if (0 == _istalpha(str.GetAt(...)))
{
}
I don't know what the problem with isalpha/iswalpha was...
Regardless, look at your for loop - no matter what the condition, the function returns.
To the compiler there's no return after the for loop. If the for loop condition fails before the
first iteration, then no value is returned. We know the for loop will always execute (because
for (int i = 0 ; i <26 ...) but the compiler doesn't.
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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the _istalpha create me a problem and while it work fine for CStrings intiliaze and valued in code
it dont work for CString (buf) from File.txt
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hmm well I never saw that code so I'm not sure why but it should work on any character you pass
to it.
There's nothing wrong with using your own function, but you probably want to fix it so
it works properly
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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