Re: [oss-security] [patch] proc.5: tell how to parse /proc/*/stat correctly

[Jakub Wilk]

* Tavis Ormandy <taviso@xxxxxxxxx>, 2022-12-28 01:50:
> > > But, really, I just don't see how this can practically be said to be 
> > > parsable...
> >
> > In its current form it never will be.  The solution is to place this 
> > variable-length field last.  Then you can "cut -d ' ' -f 51-" to get 
> > the command+args part (assuming I counted all those fields correctly 
> > ...)
> >
> > Of course, this breaks backwards compatability.
>
> I think that cut command doesn't handle newlines,

Indeed.

> There already is 'ps -q $$ -o >comm='

FWIW, "ps ... -o comm=" doesn't just print the raw comm value: it 
replaces non-printable chars with punctuation characters, and it may 
append " <defunct>" if the process is a zombie.

The easiest way to get unmangled comm is to read it from 
/proc/$PID/comm, then strip the trailing newline.

(But I suspect most /proc/*/stat parsers don't care about the comm field 
at all; they just want to skip over it to get their hands on the 
following fields.)

--
Jakub Wilk