---------- Forwarded message ----------
From: Marooth, Mark <[email protected]>
*1. **Where in the code is the 1-wire bus enumerated and the file system
created ?*
*Well, I assume you don't mean literally the filesystem. That is all in the
program owfs and responds to the FUSE calls and calls owlib in turn.*
*The filesystem is created in the owlib file ow_dir.c*
*The directory requested (I use the internal name "path") is parsed
(ow_parsename.c) into a more convenient structure (struct parsedname) that
keeps track of things like special flags (e.g. uncached) and whether the
path is a root directory or a device directory.*
*Basically there are two types of directories. Root needs to do a 1-wire
discovery process. Device directories are created from the static
information that each type of 1-wire slave has. Usually seen in a fairly
self-explanatory structure defined at the start of each device file (e.g.
ow_2408.c)*
*2. **Where in the code is the 1-wire bus polled & the file system
updated?*
*Never. 1-wire is purely an "pull" design, like a regular filesystem. You
can poll externally as much as you wish, and recent queries are cached for
efficiency, so a busy multitasking OWFS system might seem to have
pre-aquired data.*
*3. **Is it possible to separate out the FS functionality from the OW
functionality such that the FS functionality could be employed for other
protocols/devices? Best place to start?*
*Sure. I've started a rudimentary external data system (ow_external).*
*The special aspect of 1-wire is that the devices are uniquely named, and
are discoverable. Without that you need another way of getting that
information. I wish 1-wire had an embedded device description that would
make it entirely independent of embedded information. The majority of the
code is the names and extraction methods for slave properties.*
*4. **Have you done anything with other protocols?*
*Really only the other direction. The filesystem metaphor works for URLs
(owhttpd) FTP and would work for SNMP, etc.*
*I could see using a similar design for wireless sensors, etc. But there is
a lot of infrastructure to design.*
------------------------------------------------------------------------------
Rapidly troubleshoot problems before they affect your business. Most IT
organizations don't have a clear picture of how application performance
affects their revenue. With AppDynamics, you get 100% visibility into your
Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro!
http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk
_______________________________________________
Owfs-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/owfs-developers
