yaz_scan

yaz_scan

Prepares for a scan

void **yaz_scan** resource $id string $type string $startterm array $flags

This function prepares for a Z39.50 Scan Request on the specified connection.

To actually transfer the Scan Request to the server and receive the Scan Response, must be called. Upon completion of call and to handle the response. yaz_wait``yaz_wait``yaz_error``yaz_scan_result

id The connection resource returned by . yaz_connect

type Currently only type is supported. rpn

starttermStarting term point for the scan.

   The form in which the starting term is specified is given by parameter
   .
  `type`


   The syntax this parameter is similar to the RPN query as described in
   . It consists of zero or more 
   -operator specifications, then followed by 
   exactly one token.
  `yaz_search``@attr`

flags This optional parameter specifies additional information to control the behaviour of the scan request. Three indexes are currently read from the flags array: (number of terms requested), (preferred position of term) and (preferred step size). number``position``stepSize

return.void

Voorbeeld: PHP function that scans titles

<?php
function scan_titles($id, $startterm) 
{
  yaz_scan($id, "rpn", "@attr 1=4 " . $startterm);
  yaz_wait();
  $errno = yaz_errno($id);
  if ($errno == 0) {
    $ar = yaz_scan_result($id, $options);
    echo 'Scan ok; ';
    foreach ($options as $key => $val) {
      echo "$key = $val nbsp";
    }
    echo '<br /><table>';
    while (list($key, list($k, $term, $tcount)) = each($ar)) {
      if (empty($k)) continue;
      echo "<tr><td>$term</td><td>$tcount</td></tr>";
    }
    echo '</table>';
  } else {
    echo "Scan failed. Error: " . yaz_error($id) . "<br />";
  }
}
?>