Re: Explicit interpreter paths considered harmful

[Paolo Bonzini]

On 10/30/2009 01:38 PM, Eric Blake wrote:
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> According to Jim Meyering on 10/30/2009 6:29 AM:
> > > > > > +eval '(exit $?0)'&&  eval 'exec perl -wS "$0" ${1+"$@"}'
> > > > > > +&  eval 'exec /usr/bin/perl -wS "$0" $argv:q'
> > > shouldn't that be perl, rather than /usr/bin/perl?
> >
> > I could not arrange for that 2nd eval line to make a difference,
> > so figured it'd be best to leave it as is.
>
> Did you try: tcsh ./script?  I'm wondering if that second eval is catering
> to users who run SHELL=tcsh, since the script no longer has a shebang, and
> tcsh has different rules on how to attempt scripts that lack a shebang.

Yeah, that looks like it.  The "if $running_under_shell" to "if 0" is a 
change that I did too yesterday.

I'd also change -wS to -S since the script can "use warnings" if it 
wants, but shouldn't be forced to.  Some other scripts use -0777 or -T.

In the end that would be

eval '(exit $?0)'&&  eval 'exec perl -S "$0" ${1+"$@"}'
   &  eval 'exec perl -S "$0" $argv:q'
      if 0;

Paolo