[net.unix-wizards] help me with my device driver

dwaagon@sdcc6.UUCP (dragonpup) (05/06/86)

hello there,
this is the first time that i have ever written to this
news group, i hope this is the appropriate one.

i have this problem see,
i'm futility trying to write this driver for
/dev/clit for our System V machine (i realize that this comes
with a BSD version)
every time i try to load it up, the buffers seem to overflow
and alot of our circuits seem to be erroding from this.
is this a problem with "bucket" size ?
i hope someone out there can straigthen this out.

thank you very much

MKL@sri-nic.arpa (05/10/86)

A friend of mine asked me to forward this answer to Unix-Wizards...

Date: 10 May 1986 23:01:69-CDT
From: Suzie%SWAPPED@FULL.DEC
Subject: Re: help me with my device driver

> From: dragonpup <dwaagon%sdcc6.uucp@BRL.ARPA>
> Subject: help me with my device driver
> Date: 6 May 86 05:48:16 GMT
> Keywords: please, please, please
> To:       unix-wizards@brl-sem.arpa

> i have this problem see,
> i'm futility trying to write this driver for
> /dev/clit for our System V machine (i realize that this comes
> with a BSD version)
> every time i try to load it up, the buffers seem to overflow
> and alot of our circuits seem to be erroding from this.
> is this a problem with "bucket" size ?
> i hope someone out there can straigthen this out.

Writing your own driver for this device is not an easy task.  I have
used many inadequate versions, and the VMS code is probably the
hairiest around.  I suggest you find the /dev/vibrator tool as this
can be a useful aid when noone is around to help and is much better
for testing purposes than /dev/nul.  Also you should avoid any pubic
domain versions of the driver, as these may contain the Acquired
Incorrect Device Syndrome which will destroy any unprotected system.
To avoid the buffer overflow problem I suggest you skip using buffers
and access the device as quickly as possible.

Let me know if you'd like some help testing the code.
Suzie.

--------- [End of forwarded message] ---------
-------

lerner@isi-vaxa.arpa (Mitchell Lerner) (05/13/86)

I know what it's like to have trouble with a "very first time" driver,
I remember well the nerviousness and anticipation of first bringing it
up, and then, It crashes.  Dont feel like a failure!  It's just because
that it is your first time and you are so nervous and judging of yourself.
I can be of some support...  Having someone who understands these things
and is positive can be a great help in lifting this heavy load so that
you can do what you need to do.

I've never heard of these devices before.  I have alot of experience with
other devices (with both small and large buffers).  If you could tell me
more about your particular driver, perhapse we could both come up with some
solutions.

						Sincerely,

						Mitchell