Editing a text file

[chimpanzee]

Hi,
I just started learning C++ not long ago, and has been stucked at this problem for quite sometimes.

I have this text file which keep the records of cars.

00001 Toyota Camry
00002 Nissan Sunny
00003 Honda Accord
...
and so on

The problem is when i use ofstream class and try to make a modification to the line that i want to do a lazy deletion.


00002 Nissan Sunny -> xxxxxxxxxxxxxx (to indicate that this record is not a valid record)

00001 Toyota Camry
xxxxxxxxxxxxxxxxxxx
00003 Honda Accord
...
and so on

I ended up with file that has only the modification line and the rest was erased.


xxxxxxxxxxxxxxxxxx

I am using a fixed length record so i do know which byte to start the modification and where to stop.

        ofstream ofile;
	ofile.open("test.txt, ios::out);
        ofile.seekp(20);
	ofile.write("xxxxxxxxxxxxxx", 10 :confused: );
	ofile.close();

this is something that similar to the code that exists in my program.

in summary: how do i modify a part of a text file without erasing the rest of the content. Thank you in advance, I cannot proceed with the homework if i cant solve this confusion.

[Ancient Dragon]

ofile.open("test.txt, ios::out | ios::ate);

[dwks]

Your original code opened your file for write, truncuating the file (making its size zero):

ofile.open("test.txt, ios::out);

AD's code will open the file for append, which doesn't erase the file.

[chimpanzee]

Thanks a million guys. Really appreciate ur help