How can I supply pathconf with FUSE? - c

I would like to create a FUSE file system to mount tape archives. To do this correctly, I need to be able to supply replies to two pathconf keys, specifically _PC_NAME_MAX and _PC_PATH_MAX. It seems that FUSE takes the answer for the _PC_NAME_MAX key from the statfs function you provide, but I haven't found a way to set _PC_PATH_MAX. Is there a way to configure the answer to _PC_PATH_MAX? Is there in general a way to supply an answer to any pathconf call?

Further research indicates that this is not possible with FUSE at all. What a sad excuse for an API.

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Add new experimenter match field in OVS source code

I would like to add new match field of type OXM_experimenter class OVS source code, could anyone share proper document or steps to do it. It needs changes in many of the files and functions and understanding OVS source is somewhat difficult. If any added already and tested, can you guide ?
I successfully did this before, however, I don't have access to the code anymore, only bookmarks to stuff. There is an old thread in the mailing lists that may help you: Link and Link.
I wanted to handle PACKET_IN events in OVS a bit differently, so I followed the way of packets from the data plane through the upcall bit to ofproto-dpif-xlate.c. On the way, I stumbled upon a lot of constants. After adding my own to the enums, the last bit missing was the experimenter field, which was somewhere in the python scripts as described in the links above.
I hope this helps, I'm in the process of getting access to the code again I'll update my answer then. If not, the OvS discuss mailing list and archives may help you too.

How to identify device uniquely?

Firstly, I know about the duplicates. We're not talking about iOs/Android/KindOfDevice-only, as the others & cookies are not the way I want to go.
So I want to bypass the need of a password or something by "binding" my service (which is only an idea by now) to the device used.
An E-Mail and stuff would be needed of course, to keep your devices bundled.
What would your approaches be?
My thoughts so far
My first idea was using the mac-adress, because I heard that they're unique. But a quick google told me that's not really true.
On Phones I could use the phone number or the IMEI, but I don't want it to be restricted to phones, it should be usable by web, too.
I guess when we talk about a web-solution, stuff would get even more tricky because browsers won't let the service go really deep into the system and stuff?
Of course I guess there needs to be a combination of two or more things. So two not-so-unique things combine to an 99%-unique-thing?
I just need some help about how to go on with this problem, a direction, because if you google terms like "unique device identification" you only get this medicine-thing..
In my project I use
var secureUDID = (UIDevice.current.identifierForVendor?.uuidString)!
which - Returns a string created from the UUID, such as “E621E1F8-C36C-495A-93FC-0C247A3E6E5F”.
UUID - An alphanumeric string that uniquely identifies a device to the app’s vendor.

What is the correct place to list and examine ports in erl_driver

In the tutorial for erl_driver there seems to be no indication to where does the first ErlDrvPort object comes from. Say I want to wrap libusb-1.0 to use it from erlang. There is no place in the API described by ErlDrvEntry for any index methods. How does one find a port to open?
Normally you obtain the first port using the erlang:open_port/2 function, usage of which is shown in the code example in section 6.2 of the tutorial you linked to in your question.
Instead of using Ports to wrap a C library, you can also use NIFs. With Nifty there exists even a wrapper generator that does most of the work for you.

Generating an outgoing call in asterisk

I am using asterisk 11.9.0 and i want to generate an outgoing call.I found that for outgoing i have to make a .call file and place it in a var/spool/asterisk/outgoing.I am following the link below
http://the-asterisk-book.com/1.6/call-file.html#call-file-parameter
my code is same as given in the above link,the above example uses only single fixed number to call.
My problem is that
i have to generate an outgoing to a number fetched from database(outgoing to new number everytime),so how to write the code of .call file for multiple numbers outgoing and how to pass these numbers fetched from database to .call file from my extensions.conf
Is there any way to do that.
I am new to asterisk.
Any help would be appreciated.
You can use vicidial.org software to do that things.
Note, it is very bad idea do outboudn dialler-like app in asterisk without understanding asterisk logic and very-hi skills in programming/database.
For more info you also can use this page
http://www.voip-info.org/wiki/view/Asterisk+auto-dial+out
Might be easier using WombatDialer as it has a plain API where you can tell it what you want it to do and it will take care of the rest. We have a plain set up for outbound and it took maybe a couple of days from zero to what we have now. ViciDial would have been overkill.
On why rolling your own is not a great idea, the Wombat manual is quite clear: http://manuals.loway.ch/WD_UserManual-chunked/ch01.html#_why_was_wombatdialer_created
You could also use the AMI (Asterisk Manager Interface), would be easier to program with a deamon running in the back to control what gets dialed and the responses to those dials. Mora info here https://wiki.asterisk.org/wiki/pages/viewpage.action?pageId=4817239.

If I wanted to define a file format, how would I go about that?

Say I come up with some super-duper way of representing some data that I think would be useful for other people to know about and use. Assume I have a 'spec' in some form, even if it might not be a completely formal one: ie, I know how this file format will work already.
How would I then go about releasing this spec to get comments and feedback based on it? How would I get it 'standardised' in some form?
Specifying file formats is difficult. If the data you want to store is trivial, it tends to be trivial. In general however, this is hardly the case. You can use the RFC structure and keywords, but I always found specifying a fileformat in prose a slow, difficult and boring task, also because reading it is likewise difficult.
My suggestion, if you want to follow this way, is to focus on blocks of information. Most of the difficuly is for entities that are optional, and present only if another condition happens, so try to exploit this when partitioning your data.
The best spec, IMHO, is real code with an uberperfect testsuite.
As for standardization, if enough people use it, it becomes a de-facto standard. you don't need an official stamp for it, although when the format is used enough, you could benefit from an official mime type.
To talk about it, well, it depends. I found useful to talk in terms of "object oriented" entities, and also in terms of relationships. Database-like diagrams are very useful on this respect.
Finally, try to find a decent already standard alternative first, or at least try not to deal with the raw bits. There are a lot of perfect container formats out there that free you of many annoying tasks. The choice of the container depends on the actual type of file format (e.g. if you need encryption, interleaving, transactions, etc).
There are a couple of ways I'd go about it, I think.
First, determine if there's a standards body (like W3C, or IEEE) that might be related to your file format. If there is, pitch it to them. I have no idea how receptive they'd be though.
Second, a standard is useless if nobody is using it. Get some momentum behind it. Write a blog post, twitter and make a website about it. Link on programming.reddit.com, and slashdot. Describe it to your friends and colleagues. Post it here on SO, and ask for feedback.
HTH.

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