Re: File parsing issue with CFile::GetPosition() function

From:

"Doug Harrison [MVP]" <dsh@mvps.org>

Newsgroups:

microsoft.public.vc.mfc

Date:

Mon, 23 Apr 2007 13:31:14 -0500

Message-ID:

<9qup23d7ekvc56kipak09ka27apilg2o6o@4ax.com>

On Sun, 22 Apr 2007 22:14:27 -0400, Joseph M. Newcomer
<newcomer@flounder.com> wrote:

Since the files have < 4096 bytes, there seems to be little reason to consider
CFile::GetPosition at all. Just read the entire file into a string and be done with it.

EOF is not indicated by 0x1a characters (Ctrl+Z), but by running out of bytes to read. If
you have Ctrl+Z characters in the file, they are just additional characters, and do not
impact end-of-file issues.

Hard to believe, but text mode still treats Ctrl+Z as EOF.

Note that depending on the mode you are in, the file POSITION
will be the actual BYTE position, but if you are reading the file as text, the \r\n
sequence will be treated as two characters for purpose of file position but on character
for string length because the \r will be discarded.

Forget GetFilePosition. Read the whole file in and process it without any reference to
file position. 4096 bytes are infinitesimally small, and I wouldn't worry about issues of
efficiency unless you have to process several thousand of these concurrently.

That's the best approach, especially given the small amount of data.

--
Doug Harrison
Visual C++ MVP