Re: Strange sed substitution removes text

This fixes the issue for me, but I'm not sure about the motivation
behind the check.
Maybe schwarze@ can shed some light on it, since he's to (cvs) blame for
the particular line.

martijn@

On 09/24/17 15:42, Andreas Kusalananda Kähäri wrote:
> Hi,
>
> Given the input file of three lines:
>
> line 1
> line 2
> line 3
>
> and the sed script
>
> s/\</\
> /g
> s/^/hello/
>
> which inserts a newline in front of every word and then prepends the
> word "hello" to the beginning of the pattern space.
>
> The following happens:
>
> $ sed -f script.sed input.txt
> hello
>
> hello
>
> hello
>
>
> I was expecting to get
>
> hello
> line
> 1
> hello
> line
> 2
> hello
> line
> 3
>
> This is a bit surprising since running only the first sed expression
> gives (as expected)
>
>
> line
> 1
>
> line
> 2
>
> line
> 3
>
>
> The question is, why does the "line N" data disappear when inserting a
> word at the start of the pattern space here?
>
> I'm also noticing that this does not happen if a space (for instance)
> precedes the escaped newline in the first expression:
>
> s/\</ \
> /g
> s/^/hello/
>
>
> This is using sed in the base system on OpenBSD 6.1-stable (amd64).
>
> Cheers,
>