How to get the boundary in this header?
$header = 'Content-Type: multipart/report; report-type=delivery-status;'."\n"
.' boundary="9B095B5ADSN=_01D16F24CC6015F600AB1926COL004?MC5F18.ho"';
preg_match('/Content-Type:(.*)boundary="([^\"]+)"/i', $header, $match);
print_r($match);
output
9B095B5ADSN=_01D16F24CC6015F600AB1926COL004?MC5F18.ho