(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
pg_lo_tell — 返回当前大型对象的指针位置
当前查找距离大对象开头的偏移量（字节数）。如果有错误，返回值为负。
示例 #1 pg_lo_tell() 示例
<?php
$doc_oid = 189762345;
$database = pg_connect("dbname=jacarta");
pg_query($database, "begin");
$handle = pg_lo_open($database, $doc_oid, "r");
// 忽略开始的 50000 字节
pg_lo_seek($handle, 50000, PGSQL_SEEK_SET);
// 查看忽略了多少
$offset = pg_lo_tell($handle);
echo "Seek position is: $offset";
pg_query($database, "commit");
?>以上示例会输出：
Seek position is: 50000