iso9660_devread
if (!iso9660_devread(sector, 0, sizeof(*PRIMDESC), (char *)PRIMDESC))
if (!iso9660_devread(extent, 0, ISO_SECTOR_SIZE, (char *)DIRREC))
if (!iso9660_devread(ce_ptr->u.ce.extent.l, 0, ISO_SECTOR_SIZE, RRCONT_BUF))
if (!iso9660_devread(INODE->file_start + sector, blkoffset, size, buf))