uninterruptible process

[Axel M.]

Hi all,

I'm looking for system call that can make my process uninterrupted until
it completes successfully.

My app receives a SIGTERM signal (when an shutdown is triggerd), then
needs to write into a file with a simple fopen().
Actually it can't write in my file because I think it is automatically
killed (SIGKILL) by systemd.

Do you have any advice on this ?
Thanks
--
Thanks,
Axel M.