/proc/<pid>/cmdline and udhcpcd

[Laurent Bercot]

> Yes, there's still much to learn.  Do you happen to know of some
> popular examples?

  A lot of long-running processes that spawn several children and assign 
different tasks to them will do this, for informative purposes.
(I personally think that the argv of a process is not the right place 
for a user interface, and consider those daemons misguided, but still, 
it's quite a common practice.)

  Just off the top of my head:
  sshd (from openssh)
  avahi-daemon
  dovecot

and even among the good guys:
  readproctitle
  runsvdir


>> One should never assume that /proc/<pid>/cmdline will contain
>> the command line as it was originally used to execute the process.
> Do you happen to know of some reliable reference text stating that?


  int main (int argc, char **argv)

  Systems do not enforce that argv is read-only, so people *will* modify 
it. It's just as unavoidable as death, taxes, and the nervous breakdown 
of people who package systemd.

-- 
  Laurent