[LinuxPPS] PPS next steps...

[George Spelvin]

Rodolfo Giometti <giometti at enneenne.com> wrote:

> On Fri, Feb 06, 2009 at 05:53:26PM -0500, George Spelvin wrote:
>>>> Let me turn it around... what do you think "cat /dev/pps0" should do?
>>>
>>> It, eventually, should return pps0 raw data as byte stream.
>> 
>> Great!  Would you care to propose the byte stream so I can implement it?
>> What is the word size and byte order?  Is there any kind of inter-event
>> marker, or does the reader just have to count bytes?
>
> I don't need such byte stream, _you_ are the one which wish to use
> read() method. :)

Um... I want "cat /dev/pps0" to produce something useful.  I took your
first reply above to indicate that you'd like that in the future, too.
But you didn't like my suggestion for the format.  So what would
you like?

Are we arguing about whether "cat /dev/pps0" should produce something
useful?  Or about what that useful thing should look like?

> Please, propose your patch but keep in mind read(2) semantic.

I'll happily propose one, but you objected to my ideas about the format.
Should I go ahead anyway (using my format which you don't like) and we'll
argue about the format later?

>> The format can be translated.  I just think that read(2) is a more
>> convenient (although less portable) mechanism than the PPS API.
>> The intent is for it to be equivalent.
>
> I don't understand you: are telling to me that you wish to replace PPS
> API in some way? =:-o

No.  the RFC2783 interface is sacred. Even the broken bits, like the
fact that it returns ETIMEDOUT rather than EAGAIN if there is no event
ready to read.

But that's a function call interface, a library interface.

I was proposing an additional, Linux-specific (thus "less portable")
way to get at the data: cat /dev/pps0.