Re: script within find

["Alexy Khrabrov" <deliverable@xxxxxxxxx>]

A while ago, Stephane suggested a terrific script on doing things
right inside find's exec.
I'm using that magic advice and it works, fantastic!  Still it's a bit
of a mystery to me.  Why do we need {} {} twice -- although there's
only one parameter reference to $1?

Also, how would I generalize it for two commands inside the script?
Here's an example.  I want to convert a bunch of .tif files to .jpg's.
The original tifs reside in certain directory structure which should
be preserved in the target directory.

That is, we have something like

tifs/
 dir1/
   A.tif
   B.tif
 dir2/
   C.tif
 ...

And we need to create

jpgs/
 dir1/
   A.jpg
   B.jpg
 dir2/
   C.jpg
 ...

The command to do a single conversion is

convert -quality 100 dir1/A.tif /jpgs/dir1/A.jpg

-- however, we must ensure

mkdir -p /jpgs/`dirname {}` # or some such

-- before we invoke convert with the target path, to make sure it exists.

How can I stick *two* commands inside the exec in a find?

Cheers,
Alexy

On 2/24/07, Stephane Chazelas <Stephane_Chazelas@xxxxxxxx> wrote:
> On Fri, Feb 23, 2007 at 11:39:40PM -0800, Alexy Khrabrov wrote:
> > Here's a mystery solving which I've avoided for a while.  Now that I'm
> > going to publish a recipe for fixing Photoshop installation on a
> > case-sensitive Mac drive, I'd like to compress it into one script.
> >
> > The problem is, the script contains a find command, which passes all
> > things it finds via -exec to a small helper script.  The helper script
> > is necessary since it seems difficult to make -exec contain a single
> > in-line command to do it.  Here they are:
> >
> > -- the find command:
> >
> > find . -name a -exec ~/bin/fix-ps-cs2.sh {} \;
> >
> > -- the helper script, ~/bin/fix-ps-cs2.sh:
> >
> > #!/bin/sh
> > DIR=`dirname $1`
> > (cd $DIR; ln -s a A)
> >
> > as you see, it needs to invoke dirname on the argument, then create a
> > symlink in that dirname.
> >
> > Can the helper script be avoided and all the work done within the
> > single find command?
> [...]
>
> Not sure what that has to do with zsh, but on MAC OSX, I'd
> expect find to have a -execdir:
>
> find . -name a -execdir ln -s a A \;
>
> Otherwise:
>
> find . -name a -exec sh -c 'ln -s a "${1%a}A"' {} {} \;
>
> --
> Stéphane