DISKMAP(4) BSD Kernel Interfaces Manual DISKMAP(4)
diskmap -- disklabel UID mapping interface
The diskmap driver provides userland applications with a means to map a
disklabel UID to an actual device and open that device in one atomic
operation. This is achieved via the DIOCMAP ioctl(2) command.
The ability to use a disklabel UID is helpful in situations where a disk
may appear to the operating system under different device names. For
example, plugging USB keys into differently configured systems (think sd0
or sd1), or swapping between IDE and AHCI on a disk controller (wd0 or
sd0). Although the device names may change, the operating system is
still able to identify the disk by its UID.
/dev/diskmap diskmap device
The diskmap driver first appeared in OpenBSD 4.8.
The diskmap driver was written by Joel Sing.
BSD March 30, 2017 BSD