Click here to Skip to main content
15,886,919 members
Home / Discussions / C / C++ / MFC
   

C / C++ / MFC

 
GeneralRe: problem encountered by calling constructors explicitly. Pin
Tarun Jha11-May-18 11:57
Tarun Jha11-May-18 11:57 
AnswerRe: problem encountered by calling constructors explicitly. Pin
CPallini12-May-18 4:13
mveCPallini12-May-18 4:13 
Questionvs2005 Form window Error C2039 Pin
jimNLX11-May-18 6:31
jimNLX11-May-18 6:31 
AnswerRe: vs2005 Form window Error C2039 Pin
Victor Nijegorodov11-May-18 7:23
Victor Nijegorodov11-May-18 7:23 
GeneralRe: vs2005 Form window Error C2039 Pin
jimNLX11-May-18 7:28
jimNLX11-May-18 7:28 
GeneralRe: vs2005 Form window Error C2039 Pin
Victor Nijegorodov11-May-18 8:07
Victor Nijegorodov11-May-18 8:07 
QuestionWhy do I need typecast hex? Pin
Vaclav_11-May-18 5:18
Vaclav_11-May-18 5:18 
AnswerRe: Why do I need typecast hex? Pin
Richard MacCutchan11-May-18 6:25
mveRichard MacCutchan11-May-18 6:25 
Vaclav_ wrote:
char *TXBuffer = (char*) 0x04;
No you don't need to do that, and you shouldn't because it is wrong. You are trying to pass the value 0x04 as the buffer address, which will cause an access violation.

If you need a buffer containing the hex value, and you want to send that buffer's address to a function then you need to do one or other of the following:
C++
unsigned char TXBuffer = 0x04; // a single character
function(&TXBuffer); // use the addressOf operator to pass the address of the character to the function 

// or

unsigned char TXBuffer[] = { 0x04, 0 }; // multiple characters
function(TXBuffer); // TXBuffer is an array, so its name will be translated to its address by the compiler.


// the receiving function should be coded as
xxx function(unsigned char* buffer)
{
    // xxx is the return type
    // the function must know how many characters will be sent in the buffer
    // either a number that is always the same, or the length passed as a second parameter.
    // to access items from the buffer you use:
    unsigned char value = *buffer; // get the first value
    buffer++;                      // increment the pointer to the next element (if more than 1)
    value = *buffer;               // get the next value 
}

GeneralRe: Why do I need typecast hex? Pin
Vaclav_11-May-18 6:34
Vaclav_11-May-18 6:34 
Questionconst char [] and char[] difference question Pin
focusdoit10-May-18 14:26
focusdoit10-May-18 14:26 
QuestionRe: const char [] and char[] difference question Pin
David Crow10-May-18 17:22
David Crow10-May-18 17:22 
AnswerRe: const char [] and char[] difference question Pin
Richard MacCutchan10-May-18 21:25
mveRichard MacCutchan10-May-18 21:25 
AnswerRe: const char [] and char[] difference question Pin
Victor Nijegorodov10-May-18 23:03
Victor Nijegorodov10-May-18 23:03 
GeneralRe: const char [] and char[] difference question Pin
samzcs11-May-18 2:24
samzcs11-May-18 2:24 
QuestionPlease advise me on C++ coding structure Pin
Vaclav_9-May-18 4:24
Vaclav_9-May-18 4:24 
AnswerRe: Please advise me on C++ coding structure Pin
leon de boer9-May-18 4:44
leon de boer9-May-18 4:44 
QuestionHelp with C Pin
Faith Burnett5-May-18 10:28
Faith Burnett5-May-18 10:28 
AnswerRe: Help with C Pin
David Crow5-May-18 16:57
David Crow5-May-18 16:57 
GeneralRe: Help with C Pin
Faith Burnett5-May-18 19:08
Faith Burnett5-May-18 19:08 
QuestionHow to get value Pin
Vaclav_5-May-18 4:41
Vaclav_5-May-18 4:41 
AnswerRe: How to get value Pin
Richard MacCutchan5-May-18 5:47
mveRichard MacCutchan5-May-18 5:47 
GeneralRe: How to get value Pin
Vaclav_6-May-18 3:54
Vaclav_6-May-18 3:54 
GeneralRe: How to get value Pin
Richard MacCutchan6-May-18 4:48
mveRichard MacCutchan6-May-18 4:48 
GeneralRe: How to get value Pin
Vaclav_6-May-18 6:49
Vaclav_6-May-18 6:49 
QuestionWrapping c++ Pin
Member 129991324-May-18 22:48
Member 129991324-May-18 22:48 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.