#include <db.h>

int
DB->get_pagesize(DB *db, u_int32_t *pagesizep);  

The DB->get_pagesize() method returns the database's current page size, as set by the DB->set_pagesize() method. Note that if DB->set_pagesize() was not called by your application, then the default pagesize is selected based on the underlying filesystem I/O block size. If you call DB->get_pagesize() before you have opened the database, the value returned by this method is therefore the underlying filesystem I/O block size.

The DB->get_pagesize() method may be called only after the database has been opened.

The DB->get_pagesize() method returns a non-zero error value on failure and 0 on success.