Re: c++ fstream writing to existing file

From: Jerry Coffin (jcoffin_at_taeus.com)
Date: 07/24/04 

Date: 24 Jul 2004 10:39:42 -0700

ycmahesh@hotmail.com (Mahesha) wrote in message news:<3d09d707.0407231701.3d611ce5@posting.google.com>...
> Hello,
> I'm new to C++ and I have requirement to open a existing text file in
> write mode and write 2 new lines of text in the beginning of the file.
> I'm working with fstream standard library.
> If someone could direct me to a sample code to do this that would be
> really helpful.

Most file systems will only let you add to the end of a file. The
usual way to handle this is:
1. copy current file contents to a temporary file.
2. rewind the original file.
3. write your two lines to the file.
4. copy the contents from the temporary file back to the original. 

-- 
    Later,
    Jerry.
The universe is a figment of its own imagination.

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