System Programming





Kernel and system programming is the process of creating the software necessary for a computer or device to function and operate other programs. Some operating systems (such as Microsoft Windows) are proprietary, but others, such as the various Linux distributions, are open source.

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The prolema that I encounter is related to classical programming.
I want to upload an image (jpeg, gif etc) into the sql server. We did not succeed with all our efforts. If you can help me, I will remain eternally grateful
All right,
Free Tool: ZipGrep
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ZipGrep is a utility that can list and search zip (.war, .ear, .jar, etc) archives for text patterns, without the need to extract the archive's contents.

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Dual pipe producer/consumer blocked by read.

The issue is in the producer:
        read(consumer_to_producer[0], &cnt, sizeof(cnt));
        read(consumer_to_producer[0], shared_arr, sizeof(shared_arr));

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prevents the producer from working because the consumer has yet to write anything, how can I avoid this?

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#define SIZE 10

int shared_arr[SIZE];
int cnt = 0, in = 0, out = 0;
int consumer_to_producer[2], producer_to_consumer[2];

void consumer();
void producer();

int main() {
    pipe(consumer_to_producer); // consumer to producer
    pipe(producer_to_consumer); // producer to consumer

    if (fork() == 0) {
        /* child process */
    } else {
        /* parent process */


void consumer() {
    /* consumer process */
    close(producer_to_consumer[1]); // Close write end, we don't need it
    close(consumer_to_producer[0]); // This fcn doesn't need read end
    while (1) { 
        /* if buffer is full, consume it */
        // read in cnt from producer so we can check if it's full
        read(producer_to_consumer[0], &cnt, sizeof(cnt));

        if (cnt == SIZE) { /* If full, consume */
            read(producer_to_consumer[0], shared_arr, sizeof(shared_arr));
            printf("I am consuming\t%d\t%d\n", shared_arr[in], out);
            out = (out + 1) % SIZE;


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In VBA while accessing Reference, error comes 'Error accessing the system Registry'

Your solution at the following webpage not found.;en-us;269383

Please helo
What are the advantages and disadvantages of pipes ,fifo's,threads,sockets,shared memory,message queue's.And which of them i s faster?
how to open .mbz files
Hi Experts,

We have a third party system that generates a file in a FTP server every 15 min.
Now we would like to import this file into Caspio bridge.
Caspio bridge has the capability to add under scheduled tasks to import files from a FTP server.

However I'm facing the following issue.
Caspio bridge expects a fixed name file, while the system which generates files to the FTP server is set to add time stamp into the names of the files created.

Wondering what is the solution?
Perhaps you can help me put together some code that will rename files under that FTP site?
i have a existing junit file which basicaly using power mock and validating incoming messages to existings system say XYZ.  I see big XML there with bunch of tags as below

String message = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>>"
                              + "<Msg><uap>2013-09-2
++ "<id><udd>12

now i need to modify above xml with new xml generated using new xsd.

how to do that?

why xml represented as above with concatenation of + in between
any good ends to end example on this

please advise
any free tools like xpmspy which is free for generating sample xmls from XSDs and to work with XSLT etc.

I head XMLEdit but i did not see any direct link to download though?

Please advise
sms vs mms

what is differnce between above two?

please advise
when i deployed war to the webapps location of tomcat getting errors

HTTP Status 404 – Not Found
Type Status Report

Message /security-form-based/protected/index.jsp

Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.

please advise

tried below link

i am getting below error

ud_mdb_activemq\JSPLoginDemo>gradle clean build
'gradle' is not recognized as an internal or external command,
operable program or batch file.

please advise
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Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

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How to convert executable binary to shell script
Hi Experts,

I would like to copy all links displayed on a specific page, including sub-links.
For example the following
How can I accomplish that?
linux ftp script that upload files to an local server behind the same firewall, works fine manually but when the script is ran i get the following error  Please log in with USER and PASS first. getting error passive mode refused.

ftp -n -i -p test-ts <<END
user username password
Good afternoon,

I have the following doubt, I am creating a script to create a user in my Active Directory automatically with PowerShell ISE.

In the following script I want these two users to have the same password without having to type it twice, that is, when I am asked to enter the password for each user.

I want that at the moment of placing the password, I take it for these two users that I am creating as an example.

Someone who can guide me please.

Best regards.

$user = New-ADUser "Roberto"
$pwd = Read-Host "Ingresar Contraseña" -AsSecureString
$pwd = Set-ADAccountPassword Roberto -NewPassword $pwd
Enable-ADAccount Roberto
$user = New-ADUser "Rocio"
$pwd = Read-Host "Ingresar Contraseña" -AsSecureString
$pwd = Set-ADAccountPassword Rocio -NewPassword $pwd
Enable-ADAccount Rocio
Dear Experts, how can schedule set of commands in Linux program?

For example: I want to schedule a program called A running at 12.00 AM everyday; but when that A program is running, a set of commands will be executed automatically.

Please suggest.
Can I assign co line 6 to a phone number as  part of system programming I want this a a 'panic' button to call a specific outside number

what is difference between control shift L and call hierarchy(control+alt+H)  in eclipse debugging the code.
what are best debugging techniques or tips

please advise

are there any good free or cheap online training technical course without monthly fees that i have to pay. I am ok to pay some amount and use the course life time rather pay every month. please advise
Dear experts, I ' d like to become a sysadmin but what fields should I focus on? Where are the best resources to selfstudy? Can you pls suggest? Many thanks.
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I recently downloaded the new version of jaspersoft studio (6.5.0) for eclipse.  I used to be able to choose specific dates for a parameter when previewing a report, now if I pick a specific date it treats it as null.  The only values I can get to evaluate to non-null are the relative dates like "DAY" or "MONTH".

Switching to an older compatibility mode doesn't seem to work either.

DATERANGE("2017-12-22") evaluates to null when I preview.
DATERANGE("DAY") evaluates to the correct Date, 2017-12-22.

Anyone have any thoughts?

Edit: Here's the documentations on Jasper's Date Range object:
$check_email="select * form users where user email='$email'";
            $run_email = mysqli_query($con,$check_email);
            $check = mysqli_num_rows($run_email);
             echo "<script>alert('Email phone already exit,please try another!')</script>";
Tell  me some LOgic for thats..  i develop  one small console application to get remote system derive info it getting also but problem is getting only single remote machine data we have to want get mutiple remote machine data in single console application..
I have recently learned C++ and C#. That is, I have taken courses to understand the basics of them and now want to start using them for professional work. I have said I want to take on projects that push me to learn a lot more about these vast programming languages. I have a hardware device name Griffin PowerMate. It is a USB knob/wheel that can be helpful controlling a computer. For some reason, it does not have great support on Window 7, 10. It does have a driver for Window XP and Vista. I cannot get this device to do what I want in Windows 10. However, on a Mac computer, the driver is up to date and does everything I want. So, to me this proves what I want on the Windows side is possible. Is it likely to think that without an SDK from the company I could use C++ or even C# to create a driver for this device?
I have a batch script Change.bat as below  which changes value of attribute httpPort in server.xml file to a hardcoded value. But my script works only if the xml file is in the same folder where the batch script exists. BUT      
The server.xml location is %~dp0\wlp\usr\servers\defaultServer\server.xml and the batch script is in the same folder where 'wlp' folder resides. What changes do I need to do in the batch ?

server.xml contents-
<!-- Enable features -->
    <!-- <feature>localConnector-1.0</feature> -->

<!-- To access this server from a remote client add a host attribute to the following element, e.g. host="*" -->
<httpEndpoint host="*" httpPort="7680" httpsPort="9443" id="defaultHttpEndpoint"/>

<!-- Automatically expand WAR files and EAR files -->
<applicationManager autoExpand="true"/>

<applicationMonitor updateTrigger="mbean"/>

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Change.bat contents-
@echo off
setlocal EnableExtensions DisableDelayedExpansion

rem First check if the file to modify exists in directory of batch file.
set "XmlFile=%~dp0\wlp\usr\server.xml"
if not exist "%XmlFile%" goto EndBatch

rem Define some environment variables which are needed later.
set "NewPort=47682"
set "LineNumber="
set "LineCount=0"
set "TmpFile=%TEMP%\%~n0.tmp"

rem Search for the line containing attribute httpPort and get its
rem line number and the line itself loaded into environment 

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Hi, I had a new phone system installed and when I lift the handrest line 2 picks up and not line 1. I need CO1 to pickup by default since thats the line has unlimited calls rather then the 2nd line has pay per call. Can anyone help how to program the phone from picking up line 2 and pick up line 1.

System Programming





Kernel and system programming is the process of creating the software necessary for a computer or device to function and operate other programs. Some operating systems (such as Microsoft Windows) are proprietary, but others, such as the various Linux distributions, are open source.