BFS_BSIZE
bfs->header.data_end_byte = nsectors * BFS_BSIZE - 1;
if (write(fd, buf, BFS_BSIZE) < 0) {
memset(buf, 0, BFS_BSIZE);
inode->start_sector * BFS_BSIZE;
if (write(fd, buf, BFS_BSIZE) < 0) {
memset(buf, 0, BFS_BSIZE);
if (write(fd, buf, BFS_BSIZE) < 0) {
f->f_bsize = BFS_BSIZE;
f->f_frsize = BFS_BSIZE;
f->f_iosize = BFS_BSIZE;
vap->va_blocksize = BFS_BSIZE;
if (blk * BFS_BSIZE > bmp->bfs->data_end)