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QuestionPassing / modifying char* to/ by function. Pin
Vaclav_16-Dec-18 16:33
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AnswerRe: Passing / modifying char* to/ by function. Pin
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AnswerRe: Passing / modifying char* to/ by function. Pin
Richard MacCutchan16-Dec-18 22:30
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CPallini16-Dec-18 22:56
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GeneralRe: Passing / modifying char* to/ by function. Pin
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Vaclav_17-Dec-18 3:26
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GeneralRe: Passing / modifying char* to/ by function. Pin
Richard MacCutchan17-Dec-18 3:50
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GeneralRe: Passing / modifying char* to/ by function. Pin
leon de boer17-Dec-18 18:48
memberleon de boer17-Dec-18 18:48 
Personally code in this form I would not allow in our code base as it will lead to bleeding memory when used by others.

It is not clear that the function allocates memory, to anyone other than yourself and not being aware the function setups to use the char* pointer return and lose it ... take this basic code
CLASS_LCM1602 myCLASS_LCM1602 = .. some initialization;

/* now use your function */
std::cout << myCLASS_LCM1602.BuildMessage("Demo my Title", 10) << "\n";

That bleeds memory and the whole setup of the function encourages it because people will be tempted to feed the return char* value into functions.

For my 2 cents I would force you to use this interface for what you wanted to do .. Joe below has made the same comment.
int CLASS_LCM1602::BuildMessage(const char *title, int value, char* buffer, int bufSize)

It is much cleaner in that they pass you a buffer to fill and it's size and you return how many characters you put in the buffer.
Both you and they can be safe about handling the string becasue all sizes are known both directions.
If they want to allocate a buffer they can but they then know they have responsibility to dispose it.
It is also more flexible because you can use it on temporary stack allocated buffers .. something like this is a perfectly valid temp buffer with no allocate required.
char tempBuf[256];

As an example the actual Windows framework MFC is copying does exactly that Smile | :)
GetWindowTextA function | Microsoft Docs[^]
In vino veritas


modified 18-Dec-18 0:59am.

AnswerRe: Passing / modifying char* to/ by function. Pin
Joe Woodbury17-Dec-18 8:20
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Vaclav_17-Dec-18 11:20
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Questioneliminating lag from a chess clock Pin
Alexander Kindel16-Dec-18 4:23
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QuestionWiFi Notifications [SOLVED] Pin
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QuestionVC++ Word automation issues on Win 10 Pin
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QuestionInitializing struct (in C++) Pin
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