Re: Problem with positional output

2016-11-16 15:14:09 -0800, [email protected] [sed-users]:
> 
> 
>  Surprisingly , gnu sed --help doesn't showup the "-E" option
>  while it does take it sed -E "..." without any errors.
>  
>  BTW, the "-r" option is supposed to be doing this.
>  
> 
>  This definitely calls for an update of the GNU sed help options.
[...]

GNU sed came first with -r. Then, BSD added -E for the same
thing (which makes a lot more sense and is consistent with grep
for instance).

Then GNU grep added -E as a synonymous of -r for compatibility
with BSD but decided to leave it undocumented..

Then POSIX talked of specifying sed -E (likely to be in the next
major version).

Then GNU grep eventually documented -E (though there hasn't been
a new released since yet I beleive).

-- 
Stephane