Re: shell compatibility issues with SunOS 5.10

> Nguyen Thai Ngoc Duy writes:
> > On Wed, May 6, 2009 at 4:45 PM, Johannes Sixt wrote:
> > > Nguyen Thai Ngoc Duy schrieb:
> > >>       # normalize path:
> > >>       # multiple //; leading ./; /./; /../; trailing /
> > >>       path=$(printf '%s/\n' "$path" |
> > >>               sed -e '
> > >>                       s|//*|/|g
> > >>                       s|^\(\./\)*||
> > >>                       s|/\./|/|g
> > >>                       :start
> > >>                       s|\([^/]*\)/\.\./||
> > >>                       tstart
> > >>                       s|/*$||
> > >>               ')
> 
> > It says nothing. The result of "printf '%s\n' ./foo/bar | sed -e blah"
> > is just wrong, (i.e. "./" remains). I stripped down to "sed -e
> > 's|^\(\./\)*||'", does not work. Probably due to \( \) pair. Skimmed
> > through sed manpage, seems no mention of bracket grouping.
> 
> Quoting 'info Autoconf "Limitation of Usual Tools"':
> 
>      Some `sed' implementations, e.g., Solaris, restrict the special
>      role of the asterisk to one-character regular expressions.  This
>      may lead to unexpected behavior:
> 
>           $ echo '1*23*4' | /usr/bin/sed 's/\(.\)*/x/g'
>           x2x4
>           $ echo '1*23*4' | /usr/xpg4/bin/sed 's/\(.\)*/x/g'
>           x
> 
> You can work around it in this case with
>   :again
>   s|^\./||
>   t again
> 
> BTW, you should put a space between t and the label (but not between
> : and label), POSIX requires that and some sed versions expect it.