rdclose
(void)rdclose(dev, FREAD | FWRITE, S_IFBLK, NULL);
static dev_type_close(rdclose);
.d_close = rdclose,
.d_close = rdclose,
{ "rd", rdstrategy, rdopen, rdclose, rdioctl }, /*2*/
int rdclose(struct open_file *);
static dev_type_close(rdclose);
.d_close = rdclose,
.d_close = rdclose,
(void) rdclose(dev, FREAD | FWRITE, S_IFBLK, NULL);
dev_type_close(rdclose);
.d_close = rdclose,
.d_close = rdclose,