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}'*


No need to read all text into a variable when you can just send it straight
to the screen.

On Tue, May 21, 2024 at 1:43 PM Ray Andrews <rayandrews@eastlink.ca> wrote:

> A function of mine might need to unmount someting.  If there's a problem I
> try to be helpful:
>
>
> umount -v "$mountpoint" ||
> {
>     # Helpful diagnostics if partition won't unmount:
>     echo "\nCan't unmount $mountpoint.  Is a terminal logged on?  Or is it
> one of these programs:?\n(Please wait or press '^C' to quit.)"
>
>     abc=$(lsof | grep $mountpoint)
>     abc=( ${(f)abc} )
>     for def in $abc[@]; do ghi=( ${=def} ); print --
> "$ghi[1]\t$ghi[-1]\n"; done
>     return
> }
>
> Typical run:
>
>
> % mnt ,U sda
>
> Unmounting partitions ...
> umount: /mnt/sda/1: target is busy.
>
> Can't unmount /mnt/sda/1.  Is a terminal logged on?  Or is it one of these
> programs:?
> (Please wait or press '^C' to quit.)
>
> zsh      /mnt/sda/1/EFI/BOOT
> geany    /mnt/sda/1/EFI/BOOT
> geany    /mnt/sda/1/EFI/BOOT
> geany    /mnt/sda/1/EFI/BOOT
>
> ----------------------------------------------------
>
> ... works fine but I'll bet:
>
> abc=$(lsof | grep $mountpoint)
> abc=( ${(f)abc} )
> for def in $abc[@]; do ghi=( ${=def} ); print -- "$ghi[1]\t$ghi[-1]\n";
> done
>
> ... is belabored.   Can that be streamlined?  As always my splitting is a
> problem.  I need to process line by line, but then word by word so as to
> grab just the first and last words from 'lsof' output.  I'll bet Roman can
> do all of the above in 20 characters.
>
>
>

-- 
Mark J. Reed <markjreed@gmail.com>