iPtrMap          53890 ext/sqlite3/libsqlite/sqlite3.c   Pgno iPtrMap, ret;
iPtrMap          53894 ext/sqlite3/libsqlite/sqlite3.c   iPtrMap = (pgno-2)/nPagesPerMapPage;
iPtrMap          53895 ext/sqlite3/libsqlite/sqlite3.c   ret = (iPtrMap*nPagesPerMapPage) + 2;