YAZ_SCAN(3)								 1							       YAZ_SCAN(3)

yaz_scan - Prepares for a scan

SYNOPSIS

       void yaz_scan (resource	$id, string  $type, string  $startterm, [array	$flags])

DESCRIPTION

	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, yaz_wait(3) must be called. Upon completion of
       yaz_wait(3) call yaz_error(3) and yaz_scan_result(3) to handle the response.

PARAMETERS

	      o $id
		- The connection resource returned by yaz_connect(3).

	      o $type
		- Currently only type rpn is supported.

	      o $startterm
		- Starting 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 yaz_search(3). It consists of zero or more @attr-operator specifica-
		tions, then followed by exactly one token.

	      o $flags
		- This optional parameter specifies additional information to control the behaviour of the scan request. Three	indexes  are  cur-
		rently	read  from  the  flags array: number (number of terms requested), position (preferred position of term) and stepSize (pre-
		ferred step size).

RETURN VALUES

	No value is returned.

EXAMPLES

       Example #1

	      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 />";
		}
	      }
	      ?>

PHP Documentation Group 													       YAZ_SCAN(3)