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c++mfcnewlinecfile

Checking line breaks (newline characters) with CFile

I need to check whether a file is ended with a line break or not, using CFile. What I have tried:

  1. point the file pointer at the end of the file
  2. move the pointer back by 2 units
  3. check if the pointer is pointing at \r\n

Here is my code:

cfile.SeekToEnd();
cfile.Seek(-2, CFile::current);
char buffer[2];
cfile.Read(buffer, 2);
if(buffer[0] == '\r' && buffer[1] == '\n') printf("Ended with line break!");
else printf("Not ended with line break!");

However, what I found is that the buffer gives me a \n character and a garbage character (with weird values like 204). After some research through the documentation, I found that CFile::Read only count \r\n as a single character:

For text-mode files, carriage return–linefeed pairs are counted as single characters.

I am so confused because the file pointer obviously still counts 2 characters but I cannot get both of them. Is there any method to check line break at the end of a file with CFile?

Solution

  • I solved the problem by using CFile::typeBinary when opening a file.

    It seems that CFile::typeText do something special processing carriage return–linefeed pairs (e.g. filling in a garbage character which is supposed to be a carriage return) which is not desired in my case.