In article <20101110113444.ge...@apb-laptoy.apb.alt.za>,
Alan Barrett <a...@cequrux.com> wrote:
>On Wed, 10 Nov 2010, Christoph Badura wrote:
>> On Tue, Nov 09, 2010 at 08:34:56PM +0000, Alan Barrett wrote:
>> > Modified Files:
>> > src/usr.bin/pathchk: pathchk.1
>> >
>> > Log Message:
>> > Change the ironically unafe "find . -print | xargs pathchk -p" to
>> > the safe "find . -exec pathchk -p \{\} +" in an example.
>>
>> Why not save all the forks and use "find . -print0 | xargs -0 pathchk -p"?
>
>The reason I didn't use "-print0" or "xargs -0" is that both those
>features are extensions to POSIX, whereas "-exec ... +" in standardised.
>
>"-exec ... +" and "xargs" will both accumulate many args into each
>invocation of the child program, and will both fork the same number of
>times. The version using xargs is actually less efficient, because
>there's one extra fork to run "xargs" itself, and there's extra I/O over
>the pipeline.
>
>Christos seems to have made the same mistake as you, confusing "-exec
>... \;" (which runs a separate child program for each file name) with
>"-exec ... +" (which passes many file names to each invocation of the
>child program).
Yes, I did not know about exec {} +
christos
