topic Newbie Question - MAKEDEV in Operating System - Tru64 Unix

Newbie Question - MAKEDEV

admin1979 — Thu, 02 Jul 2009 06:43:53 GMT

Hello Experts,

I am here to ask a newbie question. But i need to know this as I could not find its reference anywhere.

In order to create a device file in TRU64 older versions , they say use ,

cd /dev
./MAKEDEV rz# {Where # is (Bus X 8)+ Target}

So that it can then be accessed via device file.

So far so good. But I have came across of a command in the history where the old admin guy used following command during a disk replacement.

cd /dev/
./MAKEDEV rz20 rz20

Now the question is why 2 times?? I have no idea. And moreover I have been told that , when he used single rz20 , he was not able to add the device files.

Could someone point it out?? Any guesses?

Thanx,
admin

Re: Newbie Question - MAKEDEV

Martin Moore — Thu, 02 Jul 2009 10:45:01 GMT

You shouldn't need to specify the disk twice. I have no idea what happened with the old admin. When you run MAKEDEV, it will show you which device files it's creating, for example:

# ./MAKEDEV rz20
MAKEDEV: special file(s) for rz20:
rz20a rrz20a rz20b rrz20b rz20c rrz20c rz20d rrz20d rz20e rrz20e rz20f rrz20f rz20g rrz20g rz20h rrz20h

As you can see, I only specified rz20 once, but it created all the device files for rz20.

Martin

Re: Newbie Question - MAKEDEV

Rob Leadbeater — Thu, 02 Jul 2009 11:52:41 GMT

Hi admin,

As Martin says there is no need to specify the device twice.

If you do, the second rz20 will simply try to create the device files again, which will fail silently because they already exist.

You would usually specify two (or more) devices as arguments to MAKEDEV if you wanted to create more than one...For example:

./MAKDEV rz0 rz1 rz2

would create the files for those three disk devices.

If the command returns without showing the list of devices that it created, then they (probably) already exist.

Cheers,

Rob