From owner-freebsd-current  Sat Apr 21 13:18:47 2001
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Date: Sun, 22 Apr 2001 06:15:07 +1000 (EST)
From: Bruce Evans <bde@zeta.org.au>
X-Sender: bde@besplex.bde.org
To: Brian Somers <brian@Awfulhak.org>
Cc: Sheldon Hearn <sheldonh@uunet.co.za>,
	"Rodney W. Grimes" <freebsd@gndrsh.dnsmgr.net>,
	Brian Dean <bsd@bsdhome.com>,
	Jens Schweikhardt <schweikh@schweikhardt.net>,
	freebsd-current@FreeBSD.ORG
Subject: Re: cp -d dir patch for review (or 'xargs'?) 
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On Sat, 21 Apr 2001, Brian Somers 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
> > 
> > What's all the fuss about?
> 
> Have you tried that for values of /path/to/source with lots of files ?
> Something like
> 
>   find blah | while read i; do cp $i /dest/.; done
> 
> is better, but it runs cp too many times.

cp is a bad example, since it usually does physical i/o which is much 
slower than execve() of a program that is probably cached, especially
when the program is small and not dynamically linked.

Bruce


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