--with-error-checking=none doesn't work

[Glynn Clements]

Stephen J. Turnbull wrote:

>  >     Robert> Just out of interest, does the sed in /usr/xpg4 work correctly?
>  > 
>  > Yes, it does.  Thanks.  Adding a symlink to that version of sed from an
>  > earlier directory in PATH solves my configure problem (but see my next
>  > mail...).  I didn't want to insert /usr/xpg4/bin at the start of PATH for
>  > fear of changing something else.
>  > 
>  > Just for completeness, /usr/ucb/sed does not work.
> 
> Thank you both very much for this analysis.
> 
> I suppose that the '?' construct is understood by basically all seds?
> Using '\{0,1\}' instead of '?' seems like asking for trouble....
> 
> I'll check the autoconf portability docs and see what they say, but if
> anyone has any random information on sed script portability I'd love
> to hear it.

According to IEEE 1003.1-2004[1], \{...\} is standard but ? or \? 
aren't.

[1] http://www.opengroup.org/onlinepubs/009695399/utilities/sed.html

    The sed utility shall support the BREs described in the Base
    Definitions volume of IEEE Std 1003.1-2001, Section 9.3, Basic
    Regular Expressions[2], with the following additions:

[2] http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap09.html#tag_09_03

The Info file for GNU sed says that \? is a GNU extension.

-- 
Glynn Clements <glynn at gclements.plus.com>