Detaching rr record from the target process?

[agentzh]

Sorry if it is something obvious, but is it possible to detach the "rr record" process from the target process? So that the target process can continue running (like a database or a web server daemon) while the recording ends successfully at the point of detachment (without terminating the target process).

Thanks!

[rocallahan]

This is quite hard to do because there is no easy way to disable our seccomp filter. PTRACE_O_SUSPEND_SECCOMP can be used while we're ptracing, but AFAIK if we stop ptracing then our filter will automatically resume (and kill the tracee pretty soon, since we can't report a syscall to the ptracer). So we're stuck ptracing the child forever.

We might be able to implement some kind of "partially detached" mode where we just do the minimum work to keep the tracee working and don't keep updating the saved recording, but it would probably be quite complicated.