Writing to file at specific

[safknw]

I'm trying to write 1 kb at start of file, file size is 5mb. I'm using QFile object, it truncate file to 1kb. I want to keep rest of file as it is. I only want to change initial 1kb. How can I do this?

[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.