UsrMove feature (was Re: FESCo meeting minutes for 2011-10-24)

[Richard W.M. Jones]

On Tue, Oct 25, 2011 at 08:39:25PM +0200, Michał Piotrowski wrote:
> 2011/10/25 Richard W.M. Jones <rjones at redhat.com>:
> > On Tue, Oct 25, 2011 at 08:33:28PM +0200, Michał Piotrowski wrote:
> >> 2011/10/25 Chris Adams <cmadams at hiwaay.net>:
> >> > Once upon a time, Michał Piotrowski <mkkp4x4 at 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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