write_to_disk
if ((error = write_to_disk(dev, offset, blksz, ehdr,
if ((error = write_to_disk(dev, offset_backup, blksz,
if ((error = write_to_disk(opts->dev, 0, blksz, ehdr, sizeof(*ehdr))) != 0) {
if ((error = write_to_disk(opts->dev, (blocks*blksz - BACKUP_HDR_OFFSET_END),
if ((error = write_to_disk(opts->dev, HDR_OFFSET_HIDDEN, blksz, hehdr,
if ((error = write_to_disk(opts->dev,
int write_to_disk(const char *dev, off_t offset, size_t blksz, void *mem,