Question about UDP behavior

I have a program that uses a UDP transmitter.
I use UDP because I specifically do not care if anyone is listening.
I use UDP OPEN with a specific port to get a CONN ID.
I use UDP WRITE with the conn ID and a specific DESTINATION IP and DESTINATION PORT when transmitting.
I use UDP CLOSE when the program quits.
This works fine - I can receive the data in the PXI box just fine.
QUESTION: If the receiver software is NOT running, does the UDP WRITE actually take up bandwidth on the net?
I can imagine that it might be spewing data out, without regard to whether anyone is listening.
I can also imagine that the receiver might post a signal saying "I'm listening", and the transmitter knows whether someone is listening or not, and doesn't transmit if no one is listening.
So, which is correct?
I'm trying to decide if I need to implement a transmitter on/off control.
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks

When last I looked into UDP it does indeed "wiggle the wire" going out of the back of your PC. What you switch/router does after that is dependent on its configuration.
Note: I got out of low-level network stuff before switch were invented so take my words with a grain of salt.
I was directed to Proceess monitor ( the below utility) when X-shooting a nasty bug by NI Support. Amoung many other things it will show you UDP messages traffic.
Just trying to help,
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction
Attachments:
ProcessMonitor.zip ‏1248 KB

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Please mark answered for helpful posts
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Hello everybody,
I have a question about the programming of a waveform's legend. I
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I went satisfied but I ve just noticed that this code
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N.B.
The
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Sincerly,PrinceJack
Attachments:
old_legend_test.llb ‏65 KB
new_legend_test.llb ‏65 KB

Hi
princejack,
Thanks for
posting on National Instruments forum.
The behavior
you have is completely normal. You can control the number of row displayed in
the legend and this rows are linked to the data you send to your graph. Thus,
if you have 3 arrays of data, let say chan1, chan2 and chan3, you can choose
which data you want to display in your graph using the property node (Active
plot and visible). But for the legend as you send 3 plots there is an array of
the plot name [chan1, chan2, chan3] and you can display 0, 1, 2 or 3 rows of
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Benjamin R.
R&D Software Development Manager
http://www.fluigent.com/
Attachments:
GraphLegend.vi ‏85 KB

Questions about PDF exporting with InDe CS5.5

Hey all,
A couple questions about exporting to PDF from the latest version of InDe.
First, I have noticed that it seems to take a lot longer to get to a PDF. Any suggestions for how to speed up the process? It took 8 minutes or so to generate a low-res PDF (for print) of a 24pp document with a few placed images and vector graphics. Wow, that's a long time to wait, especially for a proof.
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Thanks as always.

First, I have noticed that it seems to take a lot longer to get to a PDF. Any suggestions for how to speed up the process? It took 8 minutes or so to generate a low-res PDF (for print) of a 24pp document with a few placed images and vector graphics. Wow, that's a long time to wait, especially for a proof.
Yes, this is abnormally long (and too long), something is wrong. What's the full version of InDesign you are running, as reported by holding down Cmd or Control and selecting About InDesign?
Second, the background task... if I get it going on making that 8-minute PDF and then work some more on the document, what exactly is in the PDF? Usually I save before making a PDF or printing. So, is the last version saved what will be in the PDF?
Saving is not related. InDesign makes a database snapshot of your document the moment you begin the PDF export, and makes the export relative to that snapshot, regardless of edits you continue to make during the export process, and regardless of saving. Of course saving first is a good idea, for several reasons, not the least of which it sounds like something's fairly seriously wrong with your document or your InDesign installation.
We recommend you trash your preferences and export your document to IDML and see if either of those things changes this 8-minute behavior...err, assuming you're running 7.5.2.318.
(As an aside, this ability to work on the doc while generating a PDF seems kind of weird. Generally one makes a PDF for proofing, or even for printing, when all the changes have been made and everything is "final". So, I see no benefit to being able to work on my document while it's making a PDF, as I'm probably finished making revisions for the time being. I have to say that I kind of like the progress bar you get when you make an interactive PDF, as you know you can't work on the document when that's on the screen... )
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Pete L.
Addendum:
As usual, in attempting to boil this issue down to its essential elements, I left out some details that turned out to be important. The logic that causes the condition to occur looks more like:
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Message was edited by: planeski

Robert,
Attached are my sample code and cache config files. The code is a bit contrived-- it's extracted from a JUnit test case. Typically, we wouldn't re-use the same cache name in this way. What caught my eye however, was the fact that this same test case does not exhibit this behavior when running against a local cache directly (as opposed to a repl cache backed by a local cache.)
Why call release? Well, again, when running this same test case against a local cache, you have to call release or it won't work. I figured the same applied to a repl cache backed by a local cache.
Now that I understand this is more a byproduct of how my unit tests are written and not an issue with LRU eviction (as I originally thought), it's not a big deal-- more of a curiosity than a problem.
Pete L.<br><br> <b> Attachment: </b><br>coherence-cache-config.xml <br> (*To use this attachment you will need to rename 545.bin to coherence-cache-config.xml after the download is complete.)<br><br> <b> Attachment: </b><br>LruTest.java <br> (*To use this attachment you will need to rename 546.bin to LruTest.java after the download is complete.)

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2.
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Thanks a lot and have a good day,
Best regards,
Daniel N.

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A variable declaration is any statement that specifies a variables name and type. The line *int myInt;* certainly does that. A variable definition is a declaration that causes memory to be allocated for the variable. Since the previous statement does cause memory to be allocated for myInt, it does qualify as a definition.
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Third, for the part about some compilers giving a newly allocated variable a value of 0, does this apply to Xcode or any of its compilers? I assume not, but I wanted to check.
Thanks for all the help, and have a great weekend!

Tron55555 wrote:
I always thought a definition of a variable was a statement that assigned a value to a variable. If a basic declaration like "int myInt;" does allocate memory for the variable and therefore is a definition, can anyone give me an example of a declaration that does not allocate memory for the variable and therefore is not a definition?
I always like to think of a "declaration" to be something that makes no changes to the actual code, but just provides visibility so that compilation and/or linking will succeed. The "definition" allocates space.
You can declare a function to establish it in the namespace for the compiler to find but the linker needs an actual definition somewhere to link against. With a variable, you could also declare a variable as "extern int myvar;". The actual definition "int myvar;" would be somewhere else.
According to that book, both "extern int myvar;" and "int myvar;" are declarations, but only the latter is a definition. That is a valid way to look at it. Both statements 'delcare' something to the compiler, but on the second one 'define's some actual data.
First, I know that an int can be different sizes (either 4 bytes or 8 bytes, I think), but what does this depend on? I thought it depended on the compiler, but the above quote makes it sound like it depends on the IDE, Xcode. Which is it?
An "int" is supposed to be a processor's "native" size and the most efficient data type to use. A compiler may or may not be able to change that, depending on the target and the compiler. If a compiler supports that option and Xcode supports that compiler and that option, then Xcode can control it, via the compiler.
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I think that "setting" is just not specifying any option to explicitly set the size. You can use "-m32" or "-m64" to control this, but I wouldn't recommend it. Let Xcode handle those low-level details.
Third, for the part about some compilers giving a newly allocated variable a value of 0, does this apply to Xcode or any of its compilers? I assume not, but I wanted to check.
I don't know for sure. Why would you ask? Are you thinking of including 45 lines of macro declarations 3 levels deep to initialize values based on whether or not a particular compiler/target supports automatic initialization? Xcode current supports GCC 3.3, GCC 4.0, GCC 4.2, LLVM GCC, CLang, and Intel's compiler for building PPC, i386, and x86_64 code in both debug and release, with a large number of optimization options. It doesn't matter what compiler you use or what it's behavior is - initialize your variables in C.

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