Writing to file at specific

[wysota]

Open in QIODevice::Append mode and then seek to the beginning of the file before writing.

[safknw]

Open in QIODevice::Append mode and then seek to the beginning of the file before writing.

I don't want to append to file i want to replace 1st kb of data on file.

[wysota]

I know, but you still have to open in append mode, otherwise your file will be truncated. After you open in append, you can seek to the beginning of the file and replace its contents there.