sed vs gsed and \+ difference

[Jiri B]

Hi,

I can't understand a difference between OpenBSD and GNU sed when
handling '\+' (one or more).

Example:

$ echo 'tzdata-2016a-1.el7.noarch.rpm' | sed 's/\(tzdata\)\+.*/\1/'
tzdata-2016a-1.el7.noarch.rpm
$ echo 'tzdata-2016a-1.el7.noarch.rpm' | gsed 's/\(tzdata\)\+.*/\1/'
tzdata

$ echo '1123456' | sed -n '/1\+23456/p'
$ echo '1123456' | gsed -n '/1\+23456/p'
1123456

A bug or some hidden trick?

j.