The process token contains information about a user who is associated with a process, such as the recipient of a signal.
The praudit -x command shows the fields of the process token. The line in the following example is wrapped for display purposes.
<process audit-uid="-2" uid="root" gid="root" ruid="root" rgid="root" pid="567" sid="0" tid="0 0 0.0.0.0"/>