On Tue, Oct 25, 2011 at 08:39:25PM +0200, Michał Piotrowski wrote:
2011/10/25 Richard W.M. Jones <rjones(a)redhat.com>:
> On Tue, Oct 25, 2011 at 08:33:28PM +0200, Michał Piotrowski wrote:
>> 2011/10/25 Chris Adams <cmadams(a)hiwaay.net>:
>> > Once upon a time, Michał Piotrowski <mkkp4x4(a)gmail.com> said:
>> >> I created feature page
>> >>
https://fedoraproject.org/wiki/Features/F18MorePortableInterpreters
>> >
>> > I strongly object to this "feature". /bin/sh is a Unix standard
back to
>> > IIRC around 7th Edition, and there is NO good reason to break it. The
>> > "#!/usr/bin/env foo" suggested replacement has always been a hack
to
>> > work around broken systems, not something suggested for all scripts.
>>
>> What is wrong with
>> #!/usr/bin/env interpreter
>> from technical POV?
>
> This is what's wrong:
>
> $ cat > sh.sh
> #!/bin/sh
> $ cat > env.sh
> #!/usr/bin/env sh
> $ chmod +x sh.sh env.sh
> $ time for i in $(seq 1000); do ./sh.sh; done
>
> real 0m2.737s
> user 0m0.750s
> sys 0m1.519s
> $ time for i in $(seq 1000); do ./env.sh; done
>
> real 0m3.677s
> user 0m1.013s
> sys 0m2.296s
>
Yeah, it is noticeably slower - about 0,00094s.
34% slower is a more appropriate way to look at it.
Rich.
--
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