Sheldon Hearn <[EMAIL PROTECTED]> wrote:
 > On Sat, 21 Apr 2001 14:06:04 +0100, Brian Somers wrote:
 > > How do you do this in a script:
 > > 
 > >   cd /topdir; find . -type f | xargs -i {} cp {} /otherdir/.
 > 
 > for i in `find /path/to/source -type f`; do
 >         cp $i /path/to/dest/
 > done

That can overflow your shell's command line limit (at the
"for" command).  True, our /bin/sh doesn't has such a
limit, AFAIK, but there _are_ shells that do).  Apart from
that it is extremely inefficient, because it runs a "cp"
for every single file.  These are exactly the problems that
xargs is supposed to solve.

Actually I don't see any problem with Brian's approach
(provided that the -i option exists, of course).
xargs _does_ take the size of the environment into account,
as well as the size of all arguments, and it still leaves
much room (it only uses up to ARG_MAX - 2048 by default).

Oh by the way, in this particular example it is probably a
good idea to use cpio.  This will even work with our xargs
(which doesn't support -i yet):

   cd /topdir; find . -type f | cpio -dup /otherdir

should do exactly that job.

Regards
   Oliver

-- 
Oliver Fromme, secnetix GmbH & Co KG, Oettingenstr. 2, 80538 München
Any opinions expressed in this message may be personal to the author
and may not necessarily reflect the opinions of secnetix in any way.

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