Reading unknown number of bytes !

Hi all !
I am trying to read unknown number of bytes from the socket.Meanwhile I need to process the bytes depending on the message type in the header.I get messages like this header,body,header,body header,body header,body.....the message type is specified in the header.Each message type has different body size.So depending on that I have to read the next few bytes from the socket....say 300 or 600 depending the on the message type in the header.I get the bytes continioulsy like this.Since I cannot read byte by byte due performance reason is there any other way to do that.....any help will appreciated
sash

A simple workaround is to use a java.io.PushbackInputStream
Read enough bytes to get the header, parse the header bytes, and push the remainder back into the stream to be read as the body.

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Reading unkown number of bytes

Hi all !
I am trying to read unknown number of bytes from the socket.Meanwhile I need to process the bytes depending on the message type in the header.I get messages like this header,body,header,body header,body header,body.....the message type is specified in the header.Each message type has different body size.So depending on that I have to read the next few bytes from the socket....say 300 or 600 depending the on the message type in the header.I get the bytes continioulsy like this.Since I cannot read byte by byte due performance reason is there any other way to do that.....any help will appreciated
sash

Assuming you have a consistent header size and format, you can just read that in one call. I prefer sticking the size of body in the header. That way I can pluck that value out of the header and use it for the next read.

TCP Read undifined number of bytes

Hello LabVIEW RT users
I'm trying to convert a java application to my LabVIEW RT Smart Camera
In my camera I have a working TCP server which reads and writes some data to/from a robot. My problem is that in LabVIEW i have to specify who many bytes I'm reciving to get it to work. But in my Java application the BufferedReader took care of this. I can't control what the robot is sending but it could be things like these strings
GET X
SET R 1
SET X 443
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Somone who knows how I best handle this problem? I have tried to change the mode of the TCP read to CRLF but without succes

If you have 1MB if random binary data, is highly likely that there will be a CRLF embedded somewhere by chance, so that won't work. None of your vague comments and suggestions make any sense so far. This is most likely a very simple problem that you are way overthinking and trying to overengineer. Billions of bytes of variable lenght data are transmitted every second across the world and nobody else seems to have these problems.
Please be more specific about your application:
Where is the data coming from?
Is it also LabVIEW and do you have control over the sending program?
How easy is it to tell if it is binary or formatted?
Can you tell from the data pattern once an entire set is received?
how long are the pauses between datasets?
What happens to the data after it is received? (stream to disk, scan, parse, etc.)
LabVIEW Champion . Do more with less code and in less time .

How to get the number of bytes at TCP port

Hi all,
How to get the number of bytes to read at the TCp port...as someone had suggested in some forum we do read the number of bytes first and then pass this...
but we get a problem when we have FF data in this...because then it sends 2 FF data...and cause of this we skip the last data...is there any solution for the same?

Hi
In LabVIEW you don't have the same property as in serail port.
You havn't "Byte at TCPIP port".
if you developp a protocol, one soltion, is to send the size to read.
Ingénieur d'Application / Développeur LabVIEW Certifié (CLD)
Application Engineer / LabVIEW Certified Developer (CLD)

Smsy "Read System Number" customer number unknown for installation

Hi gurus,
I 'm configuring SMSY and following the steps outlined in the IMG in the basic settings and trying to configure RFC connections to/from satellite systems. In SMSY, I have 2 systems configured SMA and BIF.
tcode SMSY-> Systems -> SAP ERP -> SMA , Tab "System Data in SAP Support Portal".
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Click "Installation Data" shows data from SMP with correct installation number and correct customer number 706822.
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Click "System Data" shows data from SMP also shows correct data.
Why unable to "Read System Number" when the correct system number is read via "Installation Data" and "System Data"?
tcode SMSY->Systems->SAP ECC->BIF, Tab "System Data in SAP Support Portal".
Click "Read System Number" returns error "SAP customer number unknown for installation number 0020472810". <- Why?
Click "Installation Data" shows data from SMP with correct installation number and correct customer number 706822.
      The S-user listed under "Contact Persons" is correct one.
      The system number from SMP matches value in System Number field.
Click "System Data" shows data from SMP also shows correct data.
Why unable to read system number?
When I login to SMP with same S-user, under System Data Maintenance, the same data is displayed as in "Installation Data" and "System Data" links.

I don't know what happened. I came into work today and tested the "Read System Number" and it worked. I read thru the 2 notes you mentioned, just read now. The first notes I had already followed before opening this thread. The 2nd notes also talked about turning off BAdI implementation AI_SDK_SP_RFC_RP, of which I did a couple of days ago before opening this thread. I had turned turned off BAdI and simplified the AISUSER table and removed the customer number field, in order to get back to the "single-user number" basic setup in the IMG.
I had found the problem with the wrong contact info on the SMA system. It was wrong in the SMP system maintenance under installation data.
Thanks for your help.
-Don.

Easily read strings while tracking the number of bytes read?

Hi all,
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I currently use the following for the string processing:
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String str = null;
while ((str = in.readLine()) != null)
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}That's all fine, but the files I'm reading can be very large (multi GB) so obviously it can take a while to read them. During this time I pop up a progress bar, and attempt to track the progress of the read. The files I'm working with just now come with a header on the first line that states how many "somethings" (that I happen to be looking for) will appear in the file. I can use that number to set the maximum value for the progress bar, and update its current value as I find them.
However... I'm also about to start working with files that don't contain this information. I've thought of two ways of knowing how much work has to be done in advance of the read so the maximum value for the progress bar can be set:
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I'd like to use 2), but can't work out a way to use simple String based file parsing (as in the code above), but also be able to know how many bytes have been read so far. Using this code means I don't have to worry about end of line terminators, charset encoding, etc - the Reader does it for me.
Any suggestions?
Thanks

import javax.swing.*;
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How do I write and read a specified number of bytes using C++?

I need to send one byte commands followed by 1 or 2 byte data as well as read 1 or 2 byte commands from a RS232 device. How do I ensure that only 1 byte is sent for the commands or 2 bytes of data using VISA?

Hey BMas05,
Using VISA in C++ you can strings or bytes depending on which polymorphic version of the write you are using. One of the parameters for the VISA Write is the byte array and the number of bytes. This is if you are using the VISA classes for C++. You might have to have Measurement Studio to get these classes.
There is a really good example that installs on your computer at C:\Program Files\National Instruments\MeasurementStudio\VC\Examples\Io\Visa\Serial Visa.
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ORA-27063: number of bytes read/written is incorrect

Hello -
I am getting this error because my filesytem is at 100%:
ORA-01114: IO error writing block to file 202 (block # 423324)
ORA-27063: number of bytes read/written is incorrect
However, when I query the dba_data_files, and v$datafile views, I do not see a reference to file 202. Where can I get this information?
Thanks,
Mike

Mike,
Looks like you got a solution, however, just FYI, tempfiles are numbered starting w/ db_files+1, so, likely, your value of db_files is 200, the error occurred on your number 2 tempfile.
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TCP/IP Read - How do I find the number of bytes available

It appears that this is not directly possible. I am trying to get around
this by doing a tcp/ip buffered read with a very short timeout (0 or 1ms).
In theory it seems like I should be able to keep making the read call until
the exact number of bytes (4 in this case) pops out. It mostly works but
every so often hangs for some period of time and then resumes getting the 4
byte packets. Anybody have any idea what is going on?

The first thing I'm thinking of is that your delay is too short. Also, try to increase the packet length or use Immediate Mode (even CRLF MODE if you're transmitting text).
Another idea (if your application really needs that and you have LV / Windows) is to use MS Winsock Control (wait for DataArrival event and read BytesReceived).
Anyway, tune in your communication (packets and delays) taking in account details about your network or modem.
Good luck!

Length specified in network packet payload did not match number of bytes read; the connection has been closed.

Hello every one
I am getting this in my event log from time to time . not sure what is that ?
Is this a hacker trying to send rubbish data to SQL through the port ?
Any help is appreciated .
Length specified in network packet payload did not match number of bytes read; the connection has been closed. Please contact the vendor of the client library. [CLIENT: someip]

Thank you all for the reply ,
my server is on port 1533 . Port 1433 is closed on my server .
All the requests are coming from my own ip , i feel this is funny .
Is my server hacked then ?
Or could be my ISP doing any routine tests ?
Also is this is hack attempt , what does this hacker think he will benefit from this ? Could this bring the SQL server down ?
I was thinking about chaning port to something else , 1344 or something , u think this can be better ?

Showing dynamic and unknown number of images in SSRS report

I am using SSRS 2008. I need to display an unknown number of unspecified images on the report.
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But then how do i get the report to display the images, when I do not know the name or number of images?
Please help.

Hi dukie4lif,
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For your requirement, if the users want to get images by selecting a specific ID, this ID must be stored in database and associated with the path of those images. Otherwise the database can never query any records with this ID if it doesn’t have any ID stored.
Now we need to go to your database, create one more table or add one more column in the table which have your path stored to store those IDs, and let them associated with those path. Use a parameter in this report for users selecting IDs. Then your goal will
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Reference:
Report Parameters (Report Builder and SSRS)
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Add Listener to Unknown Number of JMenuItems

How can I add an ActionListener to each JMenuItem by cycling through an unknown number of menu items?
I have a program that prompts the user for a database, then creates a JMenu of table names based on whatever database the user selects.
This means that I don't know the table names or number of tables that will be added to the JMenu.
I need to add an ActionListener to EACH JMenuItem. The problem is that I am only able to select one table from the menu. Subsequent menu clicks (on different table names) have no affect on the output.
Here is an excerpt of my code:
ResultSet rs = md.getTables(null, null, null, types);
while (rs.next()) {
tables.add(rs.getString("table_name"));
for (Iterator i = tables.iterator(); i.hasNext(); )
String table = (String) i.next();
JMenuItem mi = new JMenuItem(table);
j1.add(mi);
mi.addActionListener(this);
[END CODE]
Thanks for any help you can give!

I got it. It turns out that I WAS setting the listeners correctly. My additonal output was "hidden" in the window. I found it by pure luck when I expanded the window size.
I added a line to remove all components from the JPanel before adding a new one and this "refresh" worked.
Thanks fot the help anyway! It is greatly appreciated.

Calls from cucm to CME not working-unknown number

hi all
we have cucm 9.1 and gateway 2911 on the side A and on the side B we have uc540 , we have configured tunnels between 2911 and uc540, calls from cucm SideA to uc540 Side B is ok and working fine. now we have one 9951 phone which gets ip from uc540 (side B) and tftp is our cucm IP.9951 phone is registered in cucm and calls from cucm to that 9951 phones are working fine. now problem is call is one sided between uc 540 local extension and ip phone 9951.
9951 which is registered on cucm can call uc 540 user but spa 504 phone which is registered on uc540 cant call to cisco 9951 phone gets error "unknown number"
i am attaching debug voice ccapi inout with this
kidnly help me to solve the issue ASAP

here is show voice register all.i am surprised to see dial peer 20002 but there is no dial peer like that i dont know where its getting this dial peer 20002.extension 2002 is registered with my call manager.
Router#sh voice register all
VOICE REGISTER GLOBAL
=====================
CONFIG [Version=8.6]
========================
Version 8.6
Mode is srst
Max-pool is 0
Max-dn is 0
Outbound-proxy is enabled and will use global configured value
Security Policy: DEVICE-DEFAULT
Forced Authorization Code Refer is enabled
timeout interdigit 0
network-locale[0] US (This is the default network locale for this box)
network-locale[1] US
network-locale[2] US
network-locale[3] US
network-locale[4] US
user-locale[0] US (This is the default user locale for this box)
user-locale[1] US
user-locale[2] US
user-locale[3] US
user-locale[4] US Active registrations : 0
Total SIP phones registered: 0
Total Registration Statistics
Registration requests : 0
Registration success : 0
Registration failed : 0
unRegister requests : 0
unRegister success : 0
unRegister failed : 0
Attempts to register
after last unregister : 0
Last register request time :
Last unregister request time :
Register success time :
Unregister success time :
VOICE REGISTER DN
=================
VOICE REGISTER POOL
===================
Router#

Output says "The number of bytes in the file are 0" but the file has bytes

Dear Java People,
Why would an output say a file has 0 bytes when upon doing a search for the file in Windows Explorer it say the file has 1 -4 kbytes ?
for example part of my output was :
"the number of bytes in TryFile3.java are 0"
caused by the following lines of code:
System.out.println("\n" + contents[i] + " is a " +
(contents.isDirectory() ? "directory" : "file\n") +
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+ "\nthe number of bytes in TryFile.java are " + myFile.length());
thank you in advance
below are the two program classes
Norman
import java.io.File;
import java.io.FilenameFilter;
import java.util.Date;
public class TryFile3
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+ "\nthe number of bytes in TryFile3.java are " + myFile.length());
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System.out.println(myDir.getName() + " is not a directory");
System.exit(0);
import java.io.File;
import java.io.FilenameFilter;
import java.util.Date;
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private String extension; // File extension filter
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this.extension = extension;
// static boolean firstTime = true;
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//the following line of code can be inserted in order to find out who called the method
// if(firstTime)
// new Throwable("starting the accept() method").printStackTrace();
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fileOK &= filename.endsWith('.' + extension);
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System.out.println("\n" + contents + " is a " +
(contents.isDirectory() ? "directory" : "file\n") +
" last modified on " + new Date(contents.lastModified())
+ "\nthe number of bytes in TryFile.java are " + myFile.length());I haven't read any of your italicized code, but perhaps there is a good reason why you have "myFile.length()" and not "contents.length()" in this line of code?

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Reading unknown number of bytes !

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