cdb interface is currently readonly

ext/dba/tests/dba_cdb_read.phpt

@@ -0,0 +1,41 @@
+--TEST--
+DBA CDB handler test (read only)
+--SKIPIF--
+<?php 
+	require_once('skipif.inc');
+	if (!in_array('cdb', dba_handlers())) die('skip CDB handler not available');
+?>
+--FILE--
+<?php
+	echo "database handler: cdb\n";
+	$handler = 'cdb';
+	$db_file = dirname(__FILE__).'/test.cdb';
+	if (($db_file=dba_open($db_file, "r", $handler))!==FALSE) {
+		$a = dba_firstkey($db_file);
+		$i=0;
+		echo "?$a";
+		while($a) {
+			$a = dba_nextkey($db_file);
+			echo $a;
+			$i++;
+		}
+		echo "\n";
+		echo $i;
+		for ($i=1; $i<5; $i++) {
+			echo dba_exists($i, $db_file) ? "Y" : "N";
+		}
+		echo "\n=";
+		echo dba_fetch(1, $db_file);
+		echo dba_fetch(2, $db_file);
+		echo dba_fetch(3, $db_file);
+		echo dba_fetch(4, $db_file);
+		dba_close($db_file);
+	} else {
+		echo "Error creating database\n";
+	}
+?>
+--EXPECT--
+database handler: cdb
+?1212314
+7YYYY
+=1234