To display holdings data set the syntax and the record format to "opac" (at least for Horizon ILS). It will give you an xml, containg <holding> elements with all info:
<?php
$z = yaz_connect(...
yaz_syntax($z, 'opac');
yaz_search($z, 'rpn', '@attr 1=4 "title%"');
yaz_wait();
$hits = yaz_hits($z);
yaz_range($z, 1, $hits);
yaz_present($z);
for($i = 1; $i <= $hits; $i++)
my_display(yaz_record($z, $i, 'opac'));
yaz_close($z);
function my_display($s)
{
$lines = explode("\n", trim($s));
var_dump($lines);
}
?>
