 There may be binary
zeros within the subject string, and indeed, using REG_STARTEND is the only
way to pass a subject string that contains a binary zero.
</p>
<p>
Whatever the value of <i>pmatch[0].rm_so</i>, the offsets of the matched string
and any captured substrings are still given relative to the start of
<i>string</i> itself. (Before PCRE2 release 10.30 these were given relative to
<i>string</i> + <i>pmatch[0].rm_so</i>, but this differs from other
implementations.)
</p>
<p>
This is a BSD extension, 