PATCH for a more-POSIX `ps', and related adventures

[Jilles Tjoelker]

On Sat, Mar 20, 2004 at 03:51:31PM -0500, Garance A Drosihn wrote:
> It started out that I just wanted to get rid of one message that
> `ps' writes to stderr in -current but not in -stable.  "As long as
> I was there", I thought I'd add support for a comma-separated list
> of processes for `ps -p' (as described in SUSv3).  Alexey Dokuchaev
> asked if this change got us much closer to POSIX/SUS.  Now it did
> get us a *little* closer, but in re-reading SUSv3 I realized that
> I didn't get it (that one option) quite as close as I would like.
> So, "as long as I was there", I figured I should try to come a
> little closer.

> Now, after about 30 consecutive "as long as I was there" small
> projects, I have an update which:
> [snip good stuff]
>     Adds the `-G gidlist' and '-g pgidlist' options of SYSv3.
>          (note that this replaced a null `-g' option...)

Old BSD ps used to exclude process group leaders unless `-g' or `-x'
were given.

>     Adds a `-R ruserlist' option, which is the same as what
>          SYSv3 describes for `-u' (we already have a `-u').
>          Amazingly, none of solaris, linux, or irix seem to
>          have any kind of `-R' option.

SUSv3 says -u selects by effective uid and -U selects by real uid.
FreeBSD -U selects by effective uid and -u is something else totally.
This is only of the (few) obstacles to SUSv3 (not XSI) compatibility
(another being the default selection). XSI level compatibility would
require a lot of POLA violation.

> [snip]
>     Fixes interactions between all these "selector options",
>          & our `-x' option (which is not mentioned in SUSv3).
>          For the selector options, I tried to meet the
>          description of: "If any are specified, the default
>          list shall be ignored and ps shall select the
>          processes represented by the inclusive OR of all
>          the selection-criteria options."

Hmm, this means the user must add `-x' if `-U', `-s', etc. are used and
he wants to see all matching processes. That's not good for writing
scripts that should work on both Solaris and FreeBSD, for example. Also,
`-U' used to imply `-x' on FreeBSD (it does not on NetBSD).

I propose making it so that `-x' is implied when any selector except
`-a' is used.

> [snip]

Jilles Tjoelker