From:	degiorgi AT inf DOT ethz DOT ch (Daniele Degiorgi)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: ftell does'nt work properly
Date:	21 Oct 1996 15:35:59 GMT
Organization:	Dept. Informatik, Swiss Federal Institute of Technology
Lines:	29
Message-ID:	<54g58v$gm1@neptune.ethz.ch>
References:	<Pine DOT SUN DOT 3 DOT 91 DOT 961016081710 DOT 21936A-100000 AT is>
Reply-To:	degiorgi AT inf DOT ethz DOT ch
NNTP-Posting-Host:	fido.inf.ethz.ch
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Some times ago I had the same problem:

Developping a small compiler I used a big file as a source library.
When I encountered an include statement within a module, I used
to save the actual position with ftell(), reading the included 
module and at the end of this I used fseek to resume reading
at the proper place.
I had a first problem with a module in the library containing
a single cr (0x0D). This seems to disturb all compilers I used
(Borland C++, Visual C++ and djgpp). After fixing it (replacing
it by blank in the file) all worked good with Borland C++ and 
Visual C++, but I still had problems with djgpp.

The final solution was to use different FILE variables reopening
the library file for each include and avoiding pairing of ftell/fseek.

The troubles caused by the presence of the character 0x0D are dued
to the fact that the ftell routine counts the presence of single
chars and not pairs of cr/lf. But, as the different documentations
warns about malfunctioning in case of presence of nonprintable characters
in text files, this may be ok.

In each case now I always try to avoid the usage of ftell/fseek in 
conjunction with DOS text files.


Daniel

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