Re: ktrace output file not showing up in fstat

[email protected] (Martin Husemann) writes:

>On Thu, Feb 05, 2026 at 07:54:30AM +0100, Edgar Fuß wrote:
>> Why does that ktrace file not show up? Because it isn't associated with 
>> a process?


>DESCRIPTION
>     fstat identifies open files.  A file is considered open by a process if
>     it was explicitly opened, is the working directory, root directory,
>     active pure text, or kernel trace file for that process. [..]

>So it sounds like a bug. Even if the original ktrace process is long gone
>and child processes have inherited the ktrace via -i, the file should
>be listed.



fstat only shows 'file descriptors' of processes. But for ktrace
the kernel opens a 'file', there is no descriptor and there is
no process that a descriptor could belong to.

You can find the associated vnode of the file with 'pstat -v',
but pstat doesn't understand tmpfs, so you cannot identify
the file from the output. A tracefile on ffs can be identified
by its inode number.