Scope and Using devices

Robert Love rml at
Tue Jun 1 13:04:05 PDT 2004

On Tue, 2004-06-01 at 21:42 +0200, David Zeuthen wrote:

> I think I mostly agree with you. 

Wow, that was easy ;)

Friday saw me completely undo my convincing from Joe - as the day grew
on I more and more believed that including writable properties that HAL
enforced were a slippery slope leading to an ever-growing scope and

Joe convened a group of other hackers to run the idea across virgin
ears.  I think we are all in agreement, now.

I think I am mostly happy with the current properties in HAL.  I coined
the settings vs. inherent property test that Joe mentioned: to see if
something would be in HAL, ask if it is a setting/option of the device
or if it is an inherent property of the device.  A corollary to that is
if it makes sense to write to the value, it is suspect.

This does not mean that I am against writable values - I like the device
key/value pair database idea; I am just against writing to values that
should somehow affect the device.

	Robert Love

hal mailing list
hal at

More information about the Hal mailing list