@PPID |
@PPID[name] : Returns the PID for the parent process of the specified name (or 0 if no match). If you have multiple copies of the same executable running, @PPID will return the parent PID for the first one it finds.
If the name argument begins with a =, it is assumed to be a PID instead of a process name.
Example:
echo %@ppid[tcc.exe]
21960