Title: check_mknod()


check_mknod() checks whether a device exists with

1) the name device, check_mknod()'s first parameter (e.g., /dev/ip0)
2) the same major device number as /dev/ip (typically 7)
3) a minor device number of minor, check_mknod()'s third parameter

If such a device exists, check_mknod() simply returns. If the device does not exist, check_mknod() creates the character device with mknod().