ps and username size

[Denys Vlasenko]

On Sunday 06 January 2008 14:16, Cristian Ionescu-Idbohrn wrote:
> On Sun, 6 Jan 2008, Denys Vlasenko wrote:
> 
> 
> > Thanks for the report. Using %-8.8s instead of %-8s fixes this.
> >
> > I am also fixing VSZ overflow with large VSZs.
> >
> > Will commit changes to svn in a minute.
> 
> Thanks.
> The attached patch properly adjusts the columns to the header and
> immitates debian ps from procps-3.2.7-5.
> 
> bb-ps (revision 20806)
> 
>   PID USER       VSZ STAT COMMAND
>     1 root      2080 S   init [2]
>     2 root         0 SW< [kthreadd]
>     3 root         0 SW< [migration/0]
>     4 root         0 SWN [ksoftirqd/0]
>     5 root         0 SW< [watchdog/0]
>     6 root         0 SW< [migration/1]
>     7 root         0 SWN [ksoftirqd/1]
>     8 root         0 SW< [watchdog/1]
>     9 root         0 SW< [events/0]

> # ps -A -o pid,user,vsz,stat,command | head
>   PID USER        VSZ STAT COMMAND
>     1 root       2080 Ss   init [2]
>     2 root          0 S<   [kthreadd]
>     3 root          0 S<   [migration/0]
>     4 root          0 SN   [ksoftirqd/0]
>     5 root          0 S<   [watchdog/0]
>     6 root          0 S<   [migration/1]
>     7 root          0 SN   [ksoftirqd/1]
>     8 root          0 S<   [watchdog/1]
>     9 root          0 S<   [events/0]

-                               len = printf("%5u %-8.8s %s %s ",
+                               len = printf("%5u %-8.8s %6s %-4s ",
                                        p->pid, user, buf6, p->state);

Re "%6s":
buf6 is always 5 chars long. With this patch, you have at least
two spaces between USER and VSZ. Not useful.

Re "%-4s":
Correct, p->state is always 3 chars. I will do it by adding
a space: "%s ".

> The current svn chops of long usernames to 8 chars.  That may create
> confusion if the output from ps is in any way used to identify process
> owners.  Users:
> 
>   'longnameA' and 'longnameB' will both be displayed as 'longname'.
> 
> Please consider replacing usernames longer than 8 chars with the
> corresponding uids.  That will make them unique in the ps list.

Good idea.
--
vda