On the original test machine I timed the sed solution, as well as `(grep
-m1 . 'file' && grep 'pattern' 'file')` and `(mapfile -n1 <'file' && echo
$MAPFILE[0] && grep 'pattern' 'file')` and `(head -n1 'file' && grep
'pattern' 'file')`. Total table of speeds.
grep (v2.20): ~1.15s
perl (v5.36.1): ~4.48s
awk (v4.0.2): ~10.81s
sed (v4.2.2): ~8.15s
grep && grep: ~1.15s
mapfile && grep: ~1.15s
head && grep: ~1.15s
I can write a shell function to make the head+grep version a little easier
to use in practice (i.e., loop over the list of files passed calling
head+grep on each one instead of calling head on the list and then grep on
the list), but I believe it would be difficult to change any options given
to grep. I still think the best combination of speed + output as I imagine
+ ease of integrating with changing grep options used is accomplished by a
new option for grep. But if there's no interest then this feature request
can be closed.
Dan
On Wed, Aug 23, 2023 at 4:23 AM Paul Jackson <[email protected]> wrote:
> oops - grep slower than awk, not the other way around,
> on these _highly_ inconclusive timings.
>
> --
> Paul Jackson
> [email protected]
>
