Data Streaming to HDD and Reading

Hi,
I have three channels at 1 KHz to 5 KHz selectable sampling rate. I would like to stream all three channels to disk in binary format with user supplied header / file name. I would like to watch data graph while continuously saving to disk and also need controls to select time duration to save data. I want to use same VI panel to read data with slider bar control. All three channels must show separate graph charts.
This is like simple data recording and reading application in same window with three channels and binary format.
Any help is highly appreciated,
Kishor
[email protected]

I would be glad to help, but your posting sounds like you would like us to write the code for you. Have you started the project and have a specific question? You may want to look at the LabVIEW shipping examples. (open labVIEW 6.1 >> help >> find examples >> fundamentals >> file input and output. There are several examples for reading and writting to file. You may also be interested in the DAQ examples to see how to aquire the signal. Your outline for the slider suggests that you also need to know how to make a control work like an indicator and vise versa. This would be done with property nodes or local variables. Look for property examples at find examples >> programatically controlling VIs >> controlling front panel objects.

Similar Messages

Create a continuous data stream from C++, and read it in LabView

Hello all.
I'm working on a project which involves connecting to a motion tracker and reading position and orientation data from it in realtime. The code to get the data is in c++, so I decided that the best way to do this would be to create a c++ DLL file which contains all the necessary functions to first connect to the device and read the data from it, and use the Call Library Function node to feed this data into Labview.
I'm having trouble though, since ideally I would like a continuous stream of data from the c++ code into Labview, and I'm not sure how to achieve this. Putting the call library function node in a while loop seems like an obvious solution, but if I do it this way I would have to reconnect to the device every time I get the data, which is quite a bit too slow.
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I'm using Labview 2010, version 10.0.
Apologies if the question is poorly phrased, many thanks for your help.
Dave
Solved!
Go to Solution.

dr8086 wrote:
This method sounds like an excellent suggestion, but I do have a few questions where I dont think I've understood fully.
From what I understand the basic premise is to use one call library function node to access a DLL which creates an instance of the device object, and passes a pointer too it into labview. Then a seperate call library function node would pass this pointer to another DLL which could access the device object, update it and read the data. This part could be in a while loop and carry on reading the data until a stop command is given.
That's it. I'm including some skeleton code as an example. I'm also including the code because I don't know how much you have experience with multi threading, so I'm showing how you'd have to use critical sections to guard the interactions between threads so that they don't lead to issues.
// exported function to access the devices
extern "C" __declspec(dllexport) int __stdcall init(uintptr_t *ptrOut)
*ptrOut= (uintptr_t)new CDevice();
return 0;
extern "C" __declspec(dllexport) int __stdcall get_data(uintptr_t ptr, double vals[], int size)
return ((CDevice*)ptr)->get_data(vals, size);
extern "C" __declspec(dllexport) int __stdcall close(uintptr_t ptr, double last_vals[], int size)
int r= ((CDevice*)ptr)->close();
((CDevice*)ptr)->get_data(last_vals, size);
delete (CDevice*)ptr;
return r;
// h file
// Represents a device
class CDevice
public:
virtual ~CDevice();
int init();
int get_data(double vals[], int size);
int close();
// only called by new thread
int ThreadProc();
private:
CRITICAL_SECTION rBufferSafe; // Needed for thread saftey
vhtTrackerEmulator *tracker;
HANDLE hThread;
double buffer[500];
int buffer_used;
bool done; // this HAS to be protected by critical section since 2 threads access it. Use a get/set method with critical sections inside
//cpp file
DWORD WINAPI DeviceProc(LPVOID lpParam)
((CDevice*)lpParam)->ThreadProc(); // Call the function to do the work
return 0;
CDevice::~CDevice()
DeleteCriticalSection(&rBufferSafe);
int CDevice::init()
tracker = new vhtTrackerEmulator();
InitializeCriticalSection(&rBufferSafe);
buffer_used= 0;
done= false;
hThread = CreateThread(NULL, 0, DeviceProc, this, 0, NULL); // this thread will now be saving data to an internal buffer
return 0;
int CDevice::get_data(double vals[], int size)
EnterCriticalSection(&rBufferSafe);
if (vals) // provides a way to get the current used buffer size
memcpy(vals, buffer, min(size, buffer_used));
int len= min(size, buffer_used);
buffer_used= 0; // Whatever wasn't read is erased
} else // just return the buffer size
int len= buffer_used;
LeaveCriticalSection(&rBufferSafe);
return len;
int CDevice::close()
done= true;
WaitForSingleObject(hThread, INFINITE); // handle timeouts etc.
delete tracker;
tracker= NULL;
return 0;
int CDevice::ThreadProc()
while (!bdone)
tracker->update();
EnterCriticalSection(&rBufferSafe);
if (buffer_used<500)
buffer[buffer_used++]= tracker->getRawData(0);
LeaveCriticalSection(&rBufferSafe);
Sleep(100);
return 0;
dr8086 wrote:
My main concern is that the object may go out of memory or be deallocated, since it wouldnt be held in any namespace or anything.
Since you create the object with new, the object won't expire until either the dll is unloaded or the process (LabVIEW) closes. So the object will stay valid between dll calls provided LabVIEW didn't unload the dll (which it does if the VIs are closed). When that happens, I'm not exactly sure what happens to live objects (i.e. if you forgot to call close), I imagine the system reclaims the memory but the device might still be open.
What I do to make sure that everything gets closed when the dll unloads before I could call close and delete the object is to everytime I create a new object in the dll I add it to a list, when the dll unloads, if the object is still on the list I delete it.
dr8086 wrote:
I also have a more general programming question about the purpose of the buffer. Would the buffer basically be a big table of position values, which are stored until they can be read into the rest of the VI?
Yes, see the example code.
However, depending on the frequency with which you need to collect data from the device you might not need this buffer at all. I.e. if you collect a sample about every 100ms then you could remove all threading and buffer related functions and instead read the data from the read function itself like this:
double CDevice::get_data()
tracker->update();
return tracker->getRawData(0);
Because you'd only need a buffer and a seperate thread if you collect data at a high frequency and you cannot lose any data.
Matt

Data streaming between server and client does not complete

Using an ad-hoc app, data streaming between server
and client does not complete as it supposed to be.
The process runs well in solaris 5.8, however under 5.9
we have found the characters stream buffer length limitation
is around 900 to 950 characters (by default we are using 3072
characters).
Example:
- We are transfering HTML file, which will be displayed
in the App client, with buffer=3072, the HTML only displayed / transfered
as xxxxxxxx characters, but with buffer=900 the HTML is displayed properly,
in this case, the only problem that we have is the file transfer will
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- There is another case, where we have to transfer information (data) as stream
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Any ideas why the change between 5.8 and 5.9 woudl cause problems?
The current app-driver that we are using is compiled using Solaris 5.6,
if possible we would like to have use of a later version, which is compiled using Solaris 5.9, do you think this will probably solve our problem?
Thanks
Paul

Does this have anything to do with Java RMI? or with Java come to think of it?

How to handle data whilst reformatting HDD and external HDD

Hi folks,
I'd like to reformat my external HDD (200GB) back to one partition from two. I'd also like to reformat my Mini's HDD (160GB) back to one partition (I don't want the windows partition).
My personal data on the Mini HDD is about 2.7GB, so that's easily put to a DVD for reinstallation afterwards, and I'm sure an archive installation will be relatively idiot proof.
The data on the external HDD is all my music and photos, plus data backups, some software, and some installers etc. In total, it's around 136GB.
With the windows partition on my Mini taking up 16GB, I have available space on the Mac formatted partition of 104GB.
I had the idea to borrow a friend's new and unused external HDD, with the thought simply to drag my data there, but it was with the promise that I reformat it back to Windows NFTS for him, which I think I find is not supported from OSX 10.4, so I can't use his kit.
Can anyone see a trick I'm missing, before I go and burn onto twenty-odd DVDs, and whilst on that subject, is there an inbuilt Mac OSX process for burning my data - I can't see a burn option from within the windows when I'm navigating to the external HDD?
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Matt

Thanks for the suggestions.
My friend already had to return the first drive, which his PC wouldn't recognise, and this unit is the replacement, straight from its sealed box, so I can't put him anywhere near that dark place again after he's done me a favour...
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I can see that I can copy a large proportion of it over to the Mini, which reduces DVD burn, but again, is there a quick DVD burn from external HDD? Can't see much of use in Disk Utility.

I need to be able to export the data from health kit and read it in something. Anything.

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2. Tried to download an excel add on. Didn't work.
3. Tried several online applications. Same result as Excel.
Somehow this data has to be able to be read by someone other than myself, on my phone.
Thanks to one and all for the many, many suggestions that I'm about to get.

sam.loomis1234
The only way out of Premiere Elements 11 is via export in video format (except for jpegs or audio under Publish+Share/Computer/Image or audio).
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And, the Premiere Elements 11 project.prel does not appear to be an After Effects supported project format
http://helpx.adobe.com/after-effects/kb/supported-file-formats-effects-cs4.html#main_head1
Have you asked this question in the Adobe After Effects Forum regarding supported formats?
http://forums.adobe.com/community/aftereffects_general_discussion
ATR

Embedding XML data file into PDF, and reading from it?

Hello guys,
Sorry, I'm new to here and new to the Acrobat and its scripting. So, maybe my questions will be a bit stupid, but please help. Thanks.
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I'm looking for a solution with Acrobat/PDF. And the picture I have in my mind is, to give people my enrollment form in PDF. And would like to embedded the class data (maybe in XML) in that same PDF, so that people won't loose a file and break the whole thing. And the PDF can use that class data to check if people have entre a class that's exist, and choose a date that's available...
Anyone have or know any good tutorial for that? and on the scripting to do that? Any hints does help. Thanks
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I know it is alot to ask, but please kindly help, Thanks :)

Once you open the file, you can't access it again until the original reference is closed. You might want to look at a functional global architecture. You use a case structure to determine how to access the data. Initialize, write, read, save are common examples of sections inside the functional global.
http://zone.ni.com/devzone/conceptd.nsf/webmain/D2E196C7416F373A862568690074C759

Using Digital I/O to generate serial data stream

Hello All,
I am in need to generate a serial data stream. HW I use is MIO-16E-10.
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I seems that if I use the wait timer the minimum pulse width I can get is
1ms. But for my application the pulses have to be shorter than that. I was
wondering about an alternative way to achive this. Any one who has worked
with a similar application please help!
Thanks in advance!
Anand.

Anand,
What you are looking to do is not possible with the digital lines on the board you have.
Depending on what other connections you have on the board, you could use one of the two analog outputs to generate your required serial data stream using pattern generation. Check the DAQ solution wizard=>Custom DAQ applications=>Analog Output=>Generate continuous sine wave. This example should give you a baseline to get started. Substitute the sine wave generator for your desired digital stream Logic 0 =0V, Logic 1=5V.
If you need more than 2 lines, or some form of handshaking, I would suggest using the PCI-6534 or (DIO-32-HS as it was previously called) This will give you the ability to generate serial data streams with timing and/or handshaking.

Input/Data Stream Help

I have a program that outputs text. I want to modify it to use a data
stream that can be read by another program. How do I go about this?
Are there any online guides where I can learn this? I have looked
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Thanks for any responses.
Ben.

I have a program that outputs text. I want to modify
it to use a data
stream that can be read by another program. How do I
go about this?Not at all. Using a data stream for text is a most inappropriate choice. Use print streams or buffered readers/writers.
Are there any online guides where I can learn this? Yes, it's called the API. It e.g. tells you what a DataOutputStream is good for.

Coherence Help standalone java program put data in cache & Servlet to Read

Hi,
I have coherence 3.4 and using Oracle Application Server 10.1.3 We are in the process of developing a Web Application and want to use Coherence for caching the data. My Coherence is also installed on the same box as Oracle Application Server 10.1.3 need some help in storing the data in the coherence and reading it through the servlet. We have standalone java program that needs to put data in the cache and through servlet want to read that and display it on the page. When running the client the data is stored in the cache but when reading it through the servlet it returns null. We have included both coherence.jar and tangosol.jar in the war file and also in the path when running the standalone java program. Started the Coherence using the below command:
C:\oracle\coherence\lib>java -cp coherence.jar -Dtangosol.coherence.cacheconfig=C:/oracle/coherence/tests/cache-config.xml com.tangosol.net.DefaultCacheServer
here is the sample config file used when starting the server above:
<?xml version="1.0"?>
<!DOCTYPE cache-config SYSTEM "cache-config.dtd">
<cache-config>
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        <cache-mapping>
            <cache-name>VirtualCache</cache-name>
            <scheme-name>default-distributed</scheme-name>
        </cache-mapping>
    </caching-scheme-mapping>
    <caching-schemes>
        
        <distributed-scheme>
            <scheme-name>default-distributed</scheme-name>
            <service-name>DistributedCache</service-name>
            <backing-map-scheme>
                <class-scheme>
                    <scheme-ref>default-backing-map</scheme-ref>
                </class-scheme>
            </backing-map-scheme>
        </distributed-scheme>
<class-scheme>
            <scheme-name>default-backing-map</scheme-name>
            <class-name>com.tangosol.util.SafeHashMap</class-name>
            </class-scheme>
</caching-schemes>
</cache-config>And here is the standalone java program to put the data in the cache:
import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;
public class PutCache {
    public PutCache() {
    public static void main(String[] args) {
        PutCache putCache = new PutCache();
        NamedCache         cache = CacheFactory.getCache("VirtualCache");
        String key = "hello";
        cache.put(key, "Hello Cache123123");
}And here is the Servlet code to read the data but it somehow returns null
import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.*;
import javax.servlet.http.*;
public class Servlet1 extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=windows-1252";
    public void init(ServletConfig config) throws ServletException {
        super.init(config);
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response) throws ServletException, IOException {response.setContentType(CONTENT_TYPE);
        PrintWriter out = response.getWriter();
        NamedCache         cache = CacheFactory.getCache("VirtualCache");
        String value = (String)cache.get("hello");
        out.println("<html>");
        out.println("<head><title>Servlet1</title></head>");
        out.println("<body>");
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        out.println("</body></html>");
        out.close();
}Is there any other configuration I need. Any help is really appreciated.
Thanks

Hi,
While starting the coherence using
C:\oracle\coherence\lib>java -cp coherence.jar -Dtangosol.coherence.cacheconfig=C:/oracle/coherence/tests/cache-config.xml com.tangosol.net.DefaultCacheServer
while running standaone jave program using the below command
java -Dtangosol.coherence.cacheconfig=C:/oracle/coherence/tests/cache-config.xml Populatecache
In the Web Application don't have any reference to cache-config.xml just using the coherence.jar & tangosol.jar.
What are the steps or configurations I need in order to connect to the same Coherence Cache. Do I need to provide some host:port for the Coherence for storing the data in the cache. How does the java client program and Web Application knows to connect to the Coherence. As currently even if I don't start the coherence server and just run the java standalone program it goes and executes fine wondering wher exactly does it persists the cache if coherence itself is not started or just adding the jars is enough. Any help is appreciated.
Thanks

Cannot send and read objects through sockets

I have these 4 classes to send objects through sockets. Message and Respond classes are just for
trials. I use their objects to send ıver the network. I do not get any compile time error or runtime error but
the code just does not send the objects. I used object input and output streams to send and read objects
in server (SOTServer) and in the client (SOTC) classes. When I execevute the server and client I can see
that the clients can connect to the server but they cannot send any objects allthough I wrote them inside the main method of client class. This code stops in the run() method but I could not find out why it
does do that. Run the program by creating 4 four classes.
Message.java
Respond.java
SOTC.java
SOTServer.java
Then execute server and then one or more clients to see what is going on.
Any ideas will be appreciated
thanks.
ASAP pls
//***********************************Message class**********************
import java.io.Serializable;
public class Message implements Serializable
private String chat;
private int client;
public Message(String s,int c)
client=c;
chat=s;
public Message()
client=0;
chat="aaaaa";
public int getClient()
return client;
public String getChat()
return chat;
//*******************************respond class*****************************
import java.io.Serializable;
public class Respond implements Serializable
private int toClient;
private String s;
public Respond()
public Respond(String s)
this.s=s;
public int gettoClient()
return toClient;
public String getMessage()
return s;
//***********************************SOTServer*********************
import java.io.*;
import java.net.*;
import java.util.Vector;
//private class
class ClientWorker extends Thread
private Socket client;
private ObjectInputStream objectinputstream;
private ObjectOutputStream objectoutputstream;
private SOTServer server;
ClientWorker(Socket socket, SOTServer ser)
client = socket;
server = ser;
System.out.println ("new client connected");
try
objectinputstream=new ObjectInputStream(client.getInputStream());
objectoutputstream=new ObjectOutputStream(client.getOutputStream());
catch(Exception e){}
public void sendToClient(Respond s)
try
objectoutputstream.writeObject(s);
objectoutputstream.flush();
catch(IOException e)
e.printStackTrace();
public void run()
do
Message fromClient;
try
fromClient =(Message) objectinputstream.readObject();
System.out.println (fromClient.getChat());
Respond r=new Respond();
server.sendMessageToAllClients(r);
System.out.println ("send all completed");
catch(ClassNotFoundException e){e.printStackTrace();}
catch(IOException ioexception1)
ioexception1.printStackTrace();
break;
Respond k=new Respond();
sendToClient(k);
}while(true);
public class SOTServer
ServerSocket server;
Vector clients;
public static void main(String args[]) throws IOException
SOTServer sotserver = new SOTServer();
sotserver.listenSocket();
SOTServer()
clients = new Vector();
System.out.println ("Server created");
public void sendMessageToAllClients(Respond str)
System.out.println ("sendToallclient");
ClientWorker client;
for (int i = 0; i < clients.size(); i++)
client = (ClientWorker) (clients.elementAt(i));
client.sendToClient(str);
public void listenSocket()
try
System.out.println ("listening socket");
server = new ServerSocket(4444, 6);
catch(IOException ioexception)
ioexception.printStackTrace();
do
try
ClientWorker clientworker=new ClientWorker(server.accept(), this);
clients.add(clientworker);
clientworker.start();
catch(IOException ioexception1)
ioexception1.printStackTrace();
while(true);
protected void finalize()
try
server.close();
catch(IOException ioexception)
ioexception.printStackTrace();
//*************************SOTC***(client class)*********************
import java.io.*;
import java.net.Socket;
import java.net.UnknownHostException;
class SOTC implements Runnable
private Socket socket;
private ObjectOutputStream output;
private ObjectInputStream input;
public void start()
try
socket= new Socket("127.0.0.1",4444);
input= new ObjectInputStream(socket.getInputStream());
output= new ObjectOutputStream(socket.getOutputStream());
catch(IOException e){e.printStackTrace();}
Thread outputThread= new Thread(this);
outputThread.start();
public void run()
try
do
Message m=new Message("sadfsa",0);
output.writeObject(m);
Respond fromServer=null;
fromServer=(Respond)input.readObject();
}while(true);
catch(NullPointerException e){run();}
catch(Exception e){e.printStackTrace();}
public SOTC()
start();
public void sendMessage(Message re)
try
Message k=new Message("sdasd",0);
output.writeObject(k);
output.flush();
catch(Exception ioexception)
ioexception.printStackTrace();
System.exit(-1);
public static void main(String args[])
SOTC sotclient = new SOTC();
try
System.out.println("client obje sonrasi main");
Message re=new Message("client ım ben mesaj bu da iste",0);
sotclient.sendMessage(re);
System.out.println ("client gonderdi mesaji");
catch(Exception e) {e.printStackTrace();}

ObjectStreams send a few bytes at construct time. The OutputStream writes a header and the InputStram reads them. The InputStream constrcutor will not return until oit reads that header. Your code is probably hanging in the InputStream constrcutor. (try and verify that by getting a thread dump)
If that is your problem, tolution is easy, construct the OutputStreams first.

I used time machine to restore on a formatted MAC. Now the HDD space has reduced by 100GB but I cannot see any of the files. How do I find and delete those 100GB data from the HDD?

I used time machine to restore on a formatted MAC. Now the HDD space has reduced by 100GB but I cannot see any of the files. How do I find and delete those 100GB data from the HDD?

dglenn9000 wrote:
I created a new user account just to see if it was my user Library or if there was something wrong with my system. And the new user account is doing most of the same things so I will need to do a full restore anyway.
Not necessarily. I'd suggest downloading and installing the "combo" update. That's a combination (thus the clever name) of all the updates to Leopard since it was first released, so installing it should fix anything that's gone wrong since then, such as with one of the normal "point" updates. Info and download available at: http://support.apple.com/downloads/MacOS_X_10_5_8_ComboUpdate Be sure to do a +Repair Permissions+ via Disk Utility (in your Applications/Utilities folder) afterwards.

What does the Merge Data Stream processor do when there are multiple input streams to it from the same reader?

Hi,
I have a process with a reader of master data that outputs 5 records that feeds simultaneously into 3 different lookup and return processors.
Each lookup and return processor brings some data back from a detail table. There can be multiple details so I follow each lookup processor with a split records from array processor. Hence I end up with 3 'streams' of data. Stream 1 has 8 records, stream 2 has 5 records and stream 3 has 6 records.
I join all these streams to a Merge Data Streams processor.
I end up with 9 records so although the help for the Merge Data Streams processor says 'Merge Data Streams does not perform any transformation, matching, or merging of records' there is clearly some merging going on.
What is the behaviour of the merge data streams processor in this scenario?
I have added attributes and flags into each of the streams. How many records should I see and what values should the added attributes/flags have (some records show attributes/flags from all 3 streams whereas others show just those attributes/flags from one stream).
I have developed a test case simply to understand what the processor is doing but it's not obvious and furthermore it's probably unwise to develop EDQ processes where the processor behaviour is not documented and guaranteed to remain consistent. What I am trying to achieve is to bring all of a person's (the master data) various details (assignments, employers, etc.) together so we can check the data (some rules require data from multiple details).
Thanks, Nik

Cheers Mike - and for the explanation of the terms.
I think I understand now how it's supposed to work.
What I'm finding however is that when I set a flag to Y at the beginning of a path (that includes a lookup and return and then split records from array processor) that flag is showing no (i.e. an empty) value in SOME of the records shown in the subsequent MDS processor (it's fine the very last split processor before we get to the MDS but then again there are fewer records in that split processor than the MDS).
In my case there are obviously more records in the MDS processor than there were in the original reader (because the lookup and returns are configured to have unlimited maximum matches). As mentioned, the different paths return different numbers of records before being combined in the MDS. Say a reader has 5 records and path 1 returns 8 records in total including a path-specific flag (flag1, set to Y) but path 2 (that again adds its own path-specific flag (flag2, set to Y) returns just 5 records (since nothing was added from the lookups) are you saying that flag2 would show as 'Y' for all 8 records shown in the MDS?
Hopefully you would be able to see what I mean if you try to create a process like the one I've described (or I can upload a package).
Re. the purpose of the separate paths approach it is simply to allow the visualisation ('showing the working' as Neil puts it) of the different checks being carried out by the process.
This is considered one of the benefits of the tool over writing SQL queries (with outer joins, query criteria, etc.).
Also, as mentioned I was following an example that Neil put together for us to ensure that we are doing things in a 'proper' and supported way.
If we put all the lookups, etc. for all the checks into one datastream then it no longer becomes so understandable and the value of joining processors in a process over simply writing SQL becomes questionable; arguably the EDQ process in fact becomes less easy to understand than simply writing SQL.
Also, to go down this route I will need to revise the (what was previously substantially working until I revised it) processes that I have already developed.
Thanks, Nik

I am connecting an external USB HDD and I can see it on my Apple Macbook Air. BUT this drive is READ only. How can I write to it?

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Drive Partition and Format
1.Open Disk Utility in your Utilities folder.
2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.
3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed.
4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.
5. Set the format type to Mac OS Extended (Journaled.) Click on the Security button, check the button for Zero Data and click on OK to return to the Erase window.
6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.
Steps 4-6 are optional but should be used on a drive that has never been formatted before, if the format type is not Mac OS Extended, if the partition scheme has been changed, or if a different operating system (not OS X) has been installed on the drive.

Problems Reading SSL server socket data stream using readByte()

Hi I'm trying to read an SSL server socket stream using readByte(). I need to use readByte() because my program acts an LDAP proxy (receives LDAP messages from an LDAP client then passes them onto an actual LDAP server. It works fine with normal LDAP data streams but once an SSL data stream is introduced, readByte just hangs! Here is my code.....
help!!! anyone?... anyone?
1. SSL Socket is first read into " InputStream input"
public void     run()
          Authorization     auth = new Authorization();
          try     {
               InputStream     input     =     client.getInputStream();
               while     (true)
               {     StandLdapCommand command;
                    try
                         command = new StandLdapCommand(input);
                         Authorization     t = command.get_auth();
                         if (t != null )
                              auth = t;
                    catch( SocketException e )
                    {     // If socket error, drop the connection
                         Message.Info( "Client connection closed: " + e );
                         close( e );
                         break;
                    catch( EOFException e )
                    {     // If socket error, drop the connection
                         Message.Info( "Client connection close: " + e );
                         close( e );
                         break;
                    catch( Exception e )
                         //Way too many of these to trace them!
                         Message.Error( "Command not processed due to exception");
                         close( e );
                                        break;
                                        //continue;
                    processor.processBefore(auth,     command);
                                try
                                  Thread.sleep(40); //yield to other threads
                                catch(InterruptedException ie) {}
          catch     (Exception e)
               close(e);
2 Then data is sent to an intermediate function
from this statement in the function above:   command = new StandLdapCommand(input);
     public StandLdapCommand(InputStream     in)     throws IOException
          message     =     LDAPMessage.receive(in);
          analyze();
Then finally, the read function where it hangs at "int tag = (int)din.readByte(); "
public static LDAPMessage receive(InputStream is) throws IOException
    * LDAP Message Format =
    *      1. LBER_SEQUENCE                           -- 1 byte
    *      2. Length                                  -- variable length     = 3 + 4 + 5 ....
    *      3. ID                                      -- variable length
    *      4. LDAP_REQ_msg                            -- 1 byte
    *      5. Message specific structure              -- variable length
    DataInputStream din = new DataInputStream(is);
    int tag = public static LDAPMessage receive(InputStream is) throws IOException
    * LDAP Message Format =
    *      1. LBER_SEQUENCE                           -- 1 byte
    *      2. Length                                  -- variable length     = 3 + 4 + 5 ....
    *      3. ID                                      -- variable length
    *      4. LDAP_REQ_msg                            -- 1 byte
    *      5. Message specific structure              -- variable length
    DataInputStream din = new DataInputStream(is);
       int tag = (int)din.readByte();      // sequence tag// sequence tag
    ...

I suspect you are actually getting an Exception and not tracing the cause properly and then doing a sleep and then getting another Exception. Never ever catch an exception without tracing what it actually is somewhere.
Also I don't know what the sleep is supposed to be for. You will block in readByte() until something comes in, and that should be enough yielding for anybody. The sleep is just literally a waste of time.

Streaming data to disk, need help reading data into Power Spectrum/Octave vi

I'm streaming data to disk in one loop, however once this finishes I'd like to read the data into power spectrum vi/Octave analysis vi in another loop. The data from the read vi is a string and power spectrum vi needs 1d waveform. Does anyone have experience with this process?

From your general description, I gather you are streaming to a text based file (comma or tab separated spreadsheet format) and would like to analyse this data with a power spectrum or octave analysis when you finish. Since you are streaming, I assume you have a lot of data. Do you have more than one channel?
In any case, you have two simple options (and lots of complex ones). You can either read the data back from disk and convert it to a 1D array (try the Read From Spreadsheet File.vi - will get a 2D array, take the first column or the column of your choice if you have more than one channel) or you can use the Spreadsheet String to Array primitive to create an array from your text data before you save it to disk.
If your data rate is slow enough, you can analyze as you acquire and store.
Taking your data as text is very inefficient. What you really want to do is read the data as binary, use that for your analysis, and use something like the Write to Spreadsheet File.vi to save text data to disk.
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Data Streaming to HDD and Reading

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