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

Richard W.M. Jones rjones at
Tue Oct 25 18:34:35 UTC 2011

On Tue, Oct 25, 2011 at 08:33:28PM +0200, Michał Piotrowski wrote:
> 2011/10/25 Chris Adams <cmadams at>:
> > Once upon a time, Michał Piotrowski <mkkp4x4 at> said:
> >> I created feature page
> >>
> >
> > 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 >
  $ cat >
  #!/usr/bin/env sh
  $ chmod +x
  $ time for i in $(seq 1000); do ./; done
  real		  0m2.737s
  user		  0m0.750s
  sys		  0m1.519s
  $ time for i in $(seq 1000); do ./; done
  real		  0m3.677s
  user		  0m1.013s
  sys		  0m2.296s


Richard Jones, Virtualization Group, Red Hat
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