Selecting leaf directories only

Selecting leaf directories only

[Andrej Borsenkow]

**/*(/) gives me all (sub-)directories. Any easy way to get leaf directories
only? I.e. in case

foo/
  bar/
  baz/

the above gives me ``foo foo/bar foo/baz'' while I want ``foo/bar foo/baz''
only.

-andrej

Have a nice DOS!
B >>

Re: Selecting leaf directories only

[Geoff Wing]

Andrej Borsenkow <Andrej.Borsenkow@mow.siemens.ru> typed:
:**/*(/) gives me all (sub-)directories. Any easy way to get leaf directories
:only? I.e. in case
:the above gives me ``foo foo/bar foo/baz'' while I want ``foo/bar foo/baz''
:only.

*/**/*(/)

RE: Selecting leaf directories only

[Andrej Borsenkow]

>
> Andrej Borsenkow <Andrej.Borsenkow@mow.siemens.ru> typed:
> :**/*(/) gives me all (sub-)directories. Any easy way to get leaf
> directories
> :only? I.e. in case
> :the above gives me ``foo foo/bar foo/baz'' while I want ``foo/bar foo/baz''
> :only.
>
> */**/*(/)
>
>

Black magic. Awesome :-)

But it does not completely solve the problem (it does in my specific case,
thank you). It needs at least two levels; i.e. in case

foo/
  bar1/
  bar2/
baz/

it skips ``baz'' that is leaf directory as well.

-andrej

RE: Selecting leaf directories only

[Andrej Borsenkow]

> 
> Black magic. Awesome :-)
> 
> But it does not completely solve the problem (it does in my specific case,
> thank you). It needs at least two levels;

Actually, it works with exactly two levels only:

bor@itsrm2% mkdir -p foo/bar/{baz1,baz2}
bor@itsrm2% print -l */**/*(/)
foo/bar
^^^^^^^
foo/bar/baz1
foo/bar/baz2

RE: Selecting leaf directories only

[Artur Penttinen]

On Wed, 7 Feb 2001, Andrej Borsenkow wrote:

> From: Andrej Borsenkow <Andrej.Borsenkow@mow.siemens.ru>
> To: zsh-users@sunsite.auc.dk
> Subject: RE: Selecting leaf directories only
> Date: Wed, 7 Feb 2001 12:29:53 +0300
> X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0)
> X-Procmail-List: Z Shell Users Mailing List
>
> >
> > Black magic. Awesome :-)
> >
> > But it does not completely solve the problem (it does in my specific case,
> > thank you). It needs at least two levels;
>
> Actually, it works with exactly two levels only:
>
> bor@itsrm2% mkdir -p foo/bar/{baz1,baz2}
> bor@itsrm2% print -l */**/*(/)
> foo/bar
> ^^^^^^^
> foo/bar/baz1
> foo/bar/baz2

  # mkdir -p foo/bar/{baz1,baz2}
  # print -l */**/*(/)
  foo/bar
  foo/bar/baz1
  foo/bar/baz2
  # print -l */*/*(/)
  foo/bar/baz1
  foo/bar/baz2

						wbw,artur

Re: Selecting leaf directories only

[Akos Szalkai]

On Wed, Feb 07, 2001 at 10:44:31AM +0300, Andrej Borsenkow wrote:
> **/*(/) gives me all (sub-)directories. Any easy way to get leaf directories
> only? I.e. in case

Isn't it true that the link count of leaf directories is exactly 2?
Therefore I would try **/*(/l2) .

Regards,
Akos

-- 
Akos Szalkai <szalkai@2f.hu>
IT Consultant
2F 2000 Szamitastechnikai es Szolgaltato Kft.
Tel: (+36-1)-4887700  Fax: (+36-1)-4887709  WWW: http://www.2f.hu/

RE: Selecting leaf directories only

[Andrej Borsenkow]

> 
> Isn't it true that the link count of leaf directories is exactly 2?
> Therefore I would try **/*(/l2) .
> 

Yep. Now that's real black magic :-)

Re: Selecting leaf directories only

[Nadav Har'El]

On Wed, Feb 07, 2001, Andrej Borsenkow wrote about "RE: Selecting leaf directories only":
> > 
> > Isn't it true that the link count of leaf directories is exactly 2?
> > Therefore I would try **/*(/l2) .
> > 
> 
> Yep. Now that's real black magic :-)

Just watch out - the fact that the number of links of a directory is 2 plus
the number of its subdirectories, is true only on standard Unix filesystems.
If you mount a filesystem through SMB, or a CD-ROM, for example, it is no
longer true.

A relevant quote from the GNU find(1) manual that discusses this issue:
       -noleaf
              Do not optimize by assuming that  directories  con­
              tain  2  fewer  subdirectories than their hard link
              count.   This  option  is  needed  when   searching
              filesystems  that do not follow the Unix directory-
              link convention, such as CD-ROM or MS-DOS  filesys­
              tems or AFS volume mount points.  Each directory on
              a normal Unix filesystem has at least 2 hard links:
              its  name  and  its  `.'  entry.  Additionally, its
              subdirectories (if any) each  have  a  `..'   entry
              linked to that directory.  When find is examining a
              directory, after it has statted 2 fewer subdirecto­
              ries than the directory's link count, it knows that
              the rest of the entries in the directory  are  non-
              directories  (`leaf'  files in the directory tree).
              If only the files' names need to be examined, there
              is  no  need to stat them; this gives a significant
              increase in search speed.


-- 
Nadav Har'El                        |    Wednesday, Feb 7 2001, 14 Shevat 5761
nyh@math.technion.ac.il             |-----------------------------------------
Phone: +972-53-245868, ICQ 13349191 |Why do doctors call what they do
http://nadav.harel.org.il           |practice? Think about it.

RE: Selecting leaf directories only

[Andrej Borsenkow]

>
> Just watch out - the fact that the number of links of a directory is 2 plus
> the number of its subdirectories, is true only on standard Unix filesystems.


Actually, even on standard Unix filesystem root can create hard links to
directories (that depends on definition of "standard" of course. It was
possible on original Unix filesystem, I believe, it is possible on UFS but
impossible on Veritas). But I needed it for stable, well defined, environment
and link count is quite enough.

Thanks to everybdoy

-andrej