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Date: Tue, 15 Feb 2011 11:30:39 -0500
In-Reply-To: <7CD0B68CDB1B3698E9ABE60D@utd71538.local> (Paul Schmehl's message
	of "Tue, 15 Feb 2011 09:37:49 -0600")
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Subject: Re: script help
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Paul Schmehl <pschmehl_lists@tx.rr.com> writes:

> --On February 15, 2011 12:57:12 PM +0300 Peter Andreev
> <andreev.peter@gmail.com> wrote:
>
>> Use of "xargs" on many files will be much faster than "find...exec"
>> construction
>>
>> find / -type f -name copyright.htm | xargs sed -i .bak -e 's/2010/2011/g'
>>
>
> I believe you, but can you explain why this is true?  What makes xargs
> faster than exec?

Classically, exec always spun off a new process for each exec (i.e.,
every single file).

For years now, find(1) has had a POSIX-standard syntax (ending the
command with a '+' syntax for the end of an -exec line, which does
pretty much the same thing in a single command.

Sometimes, the command being used only handles one filename at a time,
and -exec is necessary.