From: pavenis AT lanet DOT lv
To: djgpp-workers AT delorie DOT com
Date: Mon, 7 May 2001 19:45:18 +0300
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Subject: libstdc++-v3: bug in handling text files for DJGPP
Cc: libstdc++@gcc.gnu.org
Message-ID: <3AF6FB4E.3915.208439A@localhost>
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Reply-To: djgpp-workers AT delorie DOT com


basic_filebuf::sync() always advances file pointer by number of bytes 
stored in buffer for output (see seekoff at end of this procedure).

It's OK for example for Linux when there is no special format for text 
files. For DOS (and perhaps also Windows) we're getting problems as 
adding CR before LF is done by fwrite() and as result sync() 
incorrectly moves current pointer back.

See following simple example:

#include <iostream>

using std::cout;

int   main (void)
{
   cout << "\n\n\n\n\n\nfoo";  cout.flush();
   cout << "bar"; cout.flush();
   return 0;
}

I used gcc-3.0 20010506 built for target i586-pc-msdosdjgpp.
After running executable I got and  redirecting
output to file, Im getting the following:
-----------------------------------------------------------------





barfoo
------------------------------------------------------------------
Or in hexadecimal form:
0D 0A 0D 0A 0D 0A 0D 0A 0D 62 61 72 66 6F 6F

Andris