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Re: pmount could perhaps be of greater utility?

On 11.05.19 14:38, Eric S Fraga wrote:
> On Saturday,  4 May 2019 at 16:43, Erik Christiansen wrote:
> >  To provide that convenient automation, I use:
> >
> >  $ which lmount
> >  lmount is a function
> >  lmount () 
> >  { 
> >      pmount $1 `e2label $1`
> >  }
> This is nice; is there an equivalent for FAT file systems?  Most of the
> devices I mount using pmount are sd cards (cameras etc.).

Pmount is just a wrapper around the standard mount program, and that
will try to guess the fs type if not specified in the invocation - as
above. That manages ext2 and ext3 without assistance, but ... Ah, yes,
with a vfat stick it gives:

$ lmount /dev/sdb1
e2label: Bad magic number in super-block while trying to open /dev/sdb1
Couldn't find valid filesystem superblock.

And "tune2fs -l /dev/sdb1" says the same. Quite what the automounter
does to overcome that, I haven't yet figured out. A quick rewrite of
the tiny wrapper wrapper does improve matters somewhat:

lmount () {                         # Mount a USB stick at /media/read_stick_label
   if [ mp=`e2label $1` ] ; then    # if e2label can grok the label.
      pmount $1 $mp
   else                             # When that fails, TRY TO
      pmount -t vfat $1 vfat        # use fs type as mountpoint, for now.

mounts vfat OK, but the "label" argument, now third, is ignored despite
being compliant with the manpage. So it falls back to mounting on
/media/sdb1 in a most wilful manner:

/dev/sdb1 on /media/sdb1 type vfat

Either I'm not holding my mouth right, or that looks like a bug.

> Thanks.

We're not home yet.