Description:
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I think OCI-Lob::read() is reading from the wrong handle when called multiple times on different lob descriptors.



Reproduce code:
---------------
sql:
create table lobtest (lobdata clob);
insert into lobtest (lobdata) values('data data data data data data data data');
insert into lobtest (lobdata) values('data2 data2 data2 data2 data2 data2 data2 data2');
commit;

php:
$conn  = oci_connect('xxx','yyy','zzz');
$stmt = oci_parse($conn, "select lobdata from lobtest");
oci_execute($stmt);

$row1 = oci_fetch_array($stmt, OCI_NUM);
$row2 = oci_fetch_array($stmt, OCI_NUM);

var_dump($row1[0]->tell());
var_dump($row1[0]->read(8192));

var_dump($row2[0]->tell());
var_dump($row2[0]->read(8192));

Expected result:
----------------
int(0)
string(39) "data data data data data data data data"
int(0)
string(0) "data2 data2 data2 data2 data2 data2 data2 data2"

Actual result:
--------------
int(0)
string(39) "data data data data data data data data"
int(39)
string(0) ""