ps: show only processes owned by root, without showing kernel threads

Question

I know how to hide kernel threads from ps:

/bin/ps --pid 2 --ppid 2 --deselect -o user:10,pid,stat,pcpu,pmem,tty,start_time,cmd

and I know how to show only processes owned by root:

/bin/ps -U root -o user:10,pid,stat,pcpu,pmem,tty,start_time,cmd

but how do I show only processes owned by root, while excluding kernel threads?

Combining the two above commands does not work:

/bin/ps --pid 2 --ppid 2 --deselect -U root -o user:10,pid,stat,pcpu,pmem,tty,start_time,cmd

Logical since deselect will apply to both pid, ppid and U specifications. I suggest you find another way to ignore kernel threads than using pid and ppid selectors deselected @StépaheChazelas answer in unix.stackexchange.com/questions/78583/… could possibly help — MC68020
– MC68020, Commented Sep 26, 2022 at 16:55

Stéphane Chazelas · Accepted Answer · 2022-09-26 17:23:50Z

2

You can always do the selection by hand using awk:

ps -o user:10,pid,stat,pcpu,pmem,tty,start_time,cmd -p $(
  ps -Ao pid= -o sid= -o uid= | awk '$2 && ! $3 {print $1}'
)

Here checking for the session id which is 0 for kernel threads.

answered Sep 26, 2022 at 17:23

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