Re: PIPE performance and calling 'time()' at the wrong time.

On Apr 29, 2010, at 9:32 AM, Hein, Nashua NH wrote:

> I'm having trouble using time() within the for loop.
> The reason I want it within is for usage during: $ perl -ne "do-stuff-
> for-each }{ report-result-at-end "
>
> good (12 seconds):
> $ perl -e "$x=-time; for (qx(type MYSCRATCH:tmp.tmp)) {$i++; $n++ if /
> hein/i;  }$x+=time; print qq($i $n $x)"
> 42979 10 12
>
> bad (0 seconds):
> $ perl -e "for (qx(type MYSCRATCH:tmp.tmp)) {$x=-time unless $i++; $n+
> + if /hein/i;  }$x+=time; print qq($i $n $x)"
> 42979 10 0


I think in the second case the loop doesn't actually start until the  
whole file has been read in and you do probably process all of it in  
less than a second.



________________________________________
Craig A. Berry
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