[Toybox] ps and top (and Android)

[Rob Landley]

On 04/29/2016 04:06 PM, enh wrote:
> sorry, hadn't had time to look until now. notes:
> 
> * the tid column seems very wrong. in particular, i see a lot of
> duplicate tids. ah, the pid/tid columns don't auto-expand and are
> truncating...
> 
> GNU: 147139 130820 ?        00:00:00 default_ThreadM
> toybox: 14713 13082 ?        00:00:00 default_ThreadM

Hmmm, this sounds like a problem for PIDs too. Let's see...

$ ps -o pid:3,user:3,cmd:3
PID USER CMD
18748 la+ bash
19147 la+ ps -o pid:3,user:3,cmd:3

Ok,  I need to mark some columns as "expand this regardless" and others
to indicate when they get truncated, and yet it truncates the cmdline at
the right edge of the screen without indicating truncation...

Hmmm... It's not quite obvious to me what the correct behavior is.
(Numeric fields expand, command lines are silently truncated,
non-command string fields do the + thing...? Maybe?)

> * your -T is (like the desktop) showing the process name for each
> thread. Android shows the thread name, which is probably what you want
> if you're asking to see the threads in the first place.

There's a thread name? Ah, the stat[2] field gets rewritten.

How about if I treat PID != TID the same as kernel threads? [stat2name]
in square brackets?

> * you say 0 for BIT when you don't know, rather than leaving it blank
> (like Android) or using '-' (like some other ps fields). i don't think
> this matters, but i've attached a patch anyway.

Applied.

> * there's a whitespace mixup in the help text for -O. patch attached.

Applied.

> * i need to send you the Android-specific cruft for scheduling policy.

Woot.

> other than that, i went through my old notes and i think everything
> else is now done. i'll get AOSP synced this afternoon (must be friday
> again!) and send you a patch for the scheduling policy names.

I'll try to figure out what to do about column expansion. (Mental note:
how does this impact top not wrapping lines and thus scrolling the
screen...)

Rob