usableSpace      59730 ext/sqlite3/libsqlite/sqlite3.c   int usableSpace;             /* Bytes in pPage beyond the header */
usableSpace      59969 ext/sqlite3/libsqlite/sqlite3.c   usableSpace = pBt->usableSize - 12 + leafCorrection;
usableSpace      59973 ext/sqlite3/libsqlite/sqlite3.c     if( subtotal > usableSpace ){
usableSpace      60299 ext/sqlite3/libsqlite/sqlite3.c       apNew[iPg]->nFree = usableSpace-szNew[iPg];