Ray,

On Tue, May 21, 2024 at 9:21 PM Ray Andrews <rayandrews@eastlink.ca> wrote:

>
> On 2024-05-21 18:48, Mark J. Reed wrote:
>
> Running *lsof* *| grep* seems a bit silly. Can't you just do *lsof
> $mountpoint*?
>
> When I want to select columns I usually reach for *awk*:
>
>  *sudo lsof $mountpoint | awk '{print $1, $NF}'*
>
>
> Beautiful, nuts' I just presumed I needed to grep for that. Much faster
> your way.  As for awk, I don't know anything about it, but googling for
> help on various issues, one sees awk coming to the rescue all the time.  I
> half way learned sed, but I think I should have learned awk. One little
> thing, can I have the first and last columns, but with a tab between, or
> some other columnizer?:
>
> COMMAND    NAME
> zsh        /mnt/sda/5/boot
> geany      /mnt/sda/5/boot
>

Maybe something like this would work for you.  Except for lsof it is all
shell code.

L=15  # insure first field reserves L columns (adjust as needed)
lsof $mountpoint | \
  while read -r line ; do
    print -- ${(r.L.. .)${=line}[1]} ${${=line}[-1]}
  done

Regards,

Jim Murphy