System Programming

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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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Hi experts, i want to change PHP to POWERBUILDER, any help please!
below the php script :

========encrypt===============
function mc_encrypt($data, $key)
{
/// make binary representasion of $key
$key = hex2bin($key);

/// check key length, must be 256 bit or 32 bytes
if (mb_strlen($key, "8bit") !== 32) {
throw new Exception("Needs a 256-bit key!"); }

// create initialization vector
$iv_size = openssl_cipher_iv_length("aes-256-cbc");
$iv = openssl_random_pseudo_bytes($iv_size);

/// encrypt
$encrypted = openssl_encrypt($data, "aes-256-cbc", $key, OPENSSL_RAW_DATA, $iv );

/// create signature, against padding oracle attacks
$signature = mb_substr(hash_hmac("sha256", $encrypted,  $key,   true),0,10,"8bit");

/// combine all, encode, and format
$encoded = chunk_split(base64_encode($signature.$iv.$encrypted));

return $encoded;
}

========decrypt===============
function mc_decrypt($str, $key)
{

/// make binary representation of $key
$key = hex2bin($key);

/// check key length, must be 256 bit or 32 bytes if (mb_strlen($key, "8bit") !== 32) {
throw new Exception("Needs a 256-bit key!"); }

/// calculate iv size
$iv_size = openssl_cipher_iv_length("aes-256-cbc");

/// breakdown parts
$decoded = base64_decode($str);
$signature = mb_substr($decoded,0,10,"8bit");
$iv = mb_substr($decoded,10,$iv_size,"8bit");
$encrypted = mb_substr($decoded,$iv_size+10,NULL,"8bit");

/// check signature, against padding oracle attack
0
private void FileDataRequest(StreamedFileDataRequest r)

{

MemoryStream m = new MemoryStream();

r = m.AsOutputStream as StreamedFileDataRequest;
}
void loop(){
StorageLibrary l = await StorageLibrary.GetLibraryAsync(FromKnownId.Pictures);

Scrollviewer scrollviewer = new Scrollviewer();

RenderTargetBitmap r = null;

 r = new RenderTargetBitmap();

                await r.RenderAsync(scrollviewer);

                

                var file0 = await l.SaveFolder.CreateFileAsync("poikidiki");

                await FileIO.WriteBufferAsync(file0, await r.GetPixelsAsync());

                Windows.Storage.Streams.IRandomAccessStream b = await file0.OpenAsync(FileAccessMode.ReadWrite);

               

                var file = await StorageFile.CreateStreamedFileAsync("effort06.jpg", new StreamedFileDataRequestedHandler(FileDataRequest),Windows.Storage.Streams.RandomAccessStreamReference.CreateFromFile(file0));





   

              
                await file.CopyAsync(l.SaveFolder);

}

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I have this:

it doesn't copy the bytes to the streamed file.

help appreciated
0
Calling all System Administrators!!

We are excited for SysAdmin Day on July 28th! To celebrate, we are compiling the best SysAdmin stories from our community. We would love the opportunity to showcase your heroic tales of crazy problems you solved to keep the tech world going in our upcoming blog piece.  

Comment below or message us before Friday July 21st at 12pm PST to have your story included.
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LVL 9

Author Comment

by:Experts Exchange
Thanks! We are looking for stories from within the EE community!
0
 
LVL 6

Expert Comment

by:Brian Matis
Not sure if this really counts, because I wasn't the SysAdmin in this scenario; instead, I was the problematic user! But here goes: back when I was a student at CalPoly, we had access to the school's UNIX system for things like our email. I had taken the C and UNIX class, so I knew my way around the command line enough to do more than just use PINE to check my email. I also really liked the SETI @ Home project, so I got the UNIX version of the client and installed it on my account on the school's system and would just let it run.

I think maybe I had it going for a month and I have no idea what sort of resources it was taking up. I imagine it wasn't really all that bad, but eventually, a SysAdmin did shut it down and told me not to do that again...

I imagine college SysAdmins have to deal with a lot of shenanigans like that! :-D
1
Hello everyone.

I've seen that what I'm trying to do which is monitoring the file IO require the use of Window File System Filter driver and I've also looked into it but was a bit hard to understands especially as I'm not a C++ developer. What I want to achieve is to be able to trap file copy, creation, as well as file sources and destinations, lets say I'm copying a file within my computer I want to get the source path of the file as well as destination path of the file and also the file name as well and if possible with the application that is sending the file.

I saw that this can also inform you if there is file access(opening of file, reading of file) this is very much important to me to also get it if possible while the request of file open is created. I wan to trap this and if the file is one of my file then I want to first work on the requested file first (decrypt).

Thank you.
0
I have installed 2 different IDM Ultrium-TD3 tape drives and in the 2nd case, I have ALSO installed the lin_tape and lin_taped (daemon).  I also have sg3_utils 1.42, built from source - all this are on x86_64 bit computers.

Many of the commands work, including sg_read_buffer for reading the cartridge memory.

The problem is, commands such as sg_read_attr/sg_write_attr (ioctl 0x8D, 0x8C) whether from a normal C program or from the sg approach, do not ever allow reading or writing the attributes - instead, it leads to an error, such as:

SG_WRITE_ATT_0803 command error: Host_status=0x05 [DID_ABORT]
Error : Write failed (try verbose opt)

I can try either generic /dev devices or /dev/IBM types of devices.  Each gives an error.  In one case, I have an idea for how to try to fix it, but I'm just wondering, is the firmware (mine is 6B20) just not implementing it?  I doubt that's the problem.  I can upload the firmware as hex code but I would like to see the source.

Also, I don't know whether or not running lintape/lintaped matters and whether or not the IBM-generic/IBM-specific/sg-generic drivers are the issue.  I'm trying to pin down what approach to go on next.  There are literally three sets of drivers.  And I don't know whether or not I should install Tivoli.

Given all the variables, I just want to know how to proceed to get to a working sg_read_attr/sg_write_attr command.  I even tried to start with the lowest numbered attribute.

I have also tried external …
0
HOW TO CONVERT * char to string (linha):

const unsigned char
*menino1 = (const unsigned char *)0;


menino1 = p - 17;

string linha = menino[1]+menino[2]+menino[3]+menino[4]+menino[5];
0
What I need is to return a single partition ID by supplying a LABEL so I can use it in a bash script.

For instance partid = somecommand DATA-BU would store the partition is in a variable.  

What sayeth the group ?

Jay
 
I have seen ls -l /dev/disk/by-label will show me ALL LABELS > Partitions as shown in this picture, however I only need a single one and I need it in a variable form.

label-info.png
0
hi,

http://codingbat.com/prob/p136950

for above challenge
Map-1 > mapAB4
prev  |  next  |  chance

Modify and return the given map as follows: if the keys "a" and "b" have values that have different lengths, then set "c" to have the longer value. If the values exist and have the same length, change them both to the empty string in the map.

mapAB4({"a": "aaa", "b": "bb", "c": "cake"}) → {"a": "aaa", "b": "bb", "c": "aaa"}
mapAB4({"a": "aa", "b": "bbb", "c": "cake"}) → {"a": "aa", "b": "bbb", "c": "bbb"}
mapAB4({"a": "aa", "b": "bbb"}) → {"a": "aa", "b": "bbb", "c": "bbb"}

what are input parameters for the method.

what is the return for it?


"a": "aaa", "b": "bb", "c": "cake"//is these are bunch of string values pretending to be key and value for a map??

please advise on how to understand and approach this challenge
0
The script below does a count of the existing folders and if the count is different the next time it runs then it will generate an Event ID. The problem that I have with the existing approach is that when a folder is purged/deleted the count is no longer valid and we will be a false positive.

Instead of the .count we need to find if a new folder has been created. I am not sure if there is a way to do it by date? or some other way so that when folders are deleted we don't get falser positives.

Basically the goal is to have a script which will run from SCOM the target machine (every 30 min) to verify if a new folder has been created in a specific path, if so then will generate an event ID. SCOM will monitor the event-id and generate an alert.

The script below works great, but we need to replace the count with something that will be more date oriented.

Thank you!

---------------

#requires -version 3
New-EventLog -LogName Application -Source "MyScript" -ErrorAction SilentlyContinue
$basecountfile = "$env:HOMEDRIVE\scripts\basecount.txt"
if (test-path -Path $basecountfile){
  # if file not found then this is the first run so there is no baseline
  # otherwise check the path and count the directories and compare against the baseline
        $previouscount = get-content -path $basecountfile
        $basecount = (get-childitem -Path \\server\folder -Recurse -Directory).count
        if ($basecount -ne $prevouscount) {
        # found a difference
         

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0
Learn how to optimize MySQL for your business need
LVL 2
Learn how to optimize MySQL for your business need

With the increasing importance of apps & networks in both business & personal interconnections, perfor. has become one of the key metrics of successful communication. This ebook is a hands-on business-case-driven guide to understanding MySQL query parameter tuning & database perf

Hi,
Using these codes (in the project),
        private static Cell InsertCellInWorksheet(string columnName, uint rowIndex, WorksheetPart worksheetPart)
        {
            Worksheet worksheet = worksheetPart.Worksheet;
            SheetData sheetData = worksheet.GetFirstChild<SheetData>();
            string cellReference = columnName + rowIndex;
            Row row;
            if (sheetData.Elements<Row>().Where(r => r.RowIndex == rowIndex).Count() != 0)
            {
                row = sheetData.Elements<Row>().Where(r => r.RowIndex == rowIndex).First();
            }
            else
            {
                row = new Row() { RowIndex = rowIndex };
                sheetData.Append(row);
            }
            if (row.Elements<Cell>().Where(c => c.CellReference.Value == columnName + rowIndex).Count() > 0)
            {
                return row.Elements<Cell>().Where(c => c.CellReference.Value == cellReference).First();
            }
            else
            {
                Cell refCell = null;
                foreach (Cell cell in row.Elements<Cell>())
                {
                    if (string.Compare(cell.CellReference.Value, cellReference, true) > 0)
                    {
                        refCell = cell;
                        break;
                    }
                }
                Cell newCell = new Cell() { CellReference = cellReference };
                row.InsertBefore(newCell, refCell);
                

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0
Hi,
Is there one example to read each message, one by one, for one specific text string, within Sent folder of Outlook?
0
I installed C++ builder 6.0 on windows 10.
when I reopen a project , my working directory don't change to new project path and my new forms create on the directory that last time I used "FILE->Open Project" method.
if every body knows how can say to it change to the project path after reopen .
-- thanks reza
0
Hi,
Further to this
https://www.experts-exchange.com/questions/29029100/Problem-to-show-list.html?anchor=a42174635¬ificationFollowed=190745230#a42174635

and I have ImageHandler.cs like
using System;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Data;
using System.Configuration;
using System.Data.OleDb;
using System.Xml;
using System.Globalization;
using System.Collections.Generic;
using System.Drawing;
using System.Text; // This was needed to make ASCIIEncoding function
using System.Security.Cryptography; // This was needed to make everything related to MD5 function
using System.Web.Services;

namespace Own_rec
{
    public class ImageHandler : IHttpHandler
    {
        /// <summary>
        /// You will need to configure this handler in the Web.config file of your 
        /// web and register it with IIS before being able to use it. For more information
        /// see the following link: http://go.microsoft.com/?linkid=8101007
        /// </summary>
        public void ProcessRequest(HttpContext context)
        {
            //string userId = string.Empty;
            int userId = 0;
            //-- get the ID from query string you get from <img src tag
            if (null != 

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0
Hi,
Using these codes

        public static List<HouseData> GetHouseList()
        {
            List<HouseData> houseList = new List<HouseData>();
            using (SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["Mssqlconn3"].ConnectionString))
            {
                using (SqlCommand sqlCmd = new SqlCommand("SELECT house_name, address1, address2, price, price_curr, raised_by_user_id FROM house_tab", sqlConn))
                {
                    sqlConn.Open();
                    sqlCmd.CommandType = CommandType.Text;
                    SqlDataAdapter sqlAd = new SqlDataAdapter(sqlCmd);
                    DataTable sqlDt = new DataTable();
                    sqlAd.Fill(sqlDt);
                    sqlConn.Close();
                    if (null != sqlDt)
                    {
                        houseList = sqlDt
                                        .AsEnumerable()
                                        .Select(dataRow => new HouseData
                                        {
                                            house_name = dataRow.Field<string>("house_name"),
                                            address1 = dataRow.Field<string>("address1"),
                                            address2 = dataRow.Field<string>("address2"),
                                            price = dataRow.Field<decimal>("price"),
                                            price_curr = 

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0
Hi,
How to adjust to list below, to have also one picture file included, that is retrieved from database?

            using (SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["Mssqlconn3"].ConnectionString))
            {
                using (SqlCommand sqlCmd = new SqlCommand("SELECT house_name, address1, address2, price, price_curr FROM house_tab", sqlConn))
                {
                    sqlConn.Open();
                    sqlCmd.CommandType = CommandType.Text;
                    SqlDataAdapter sqlAd = new SqlDataAdapter(sqlCmd);
                    DataTable sqlDt = new DataTable();
                    sqlAd.Fill(sqlDt);
                    sqlConn.Close();
                    if (null != sqlDt)
                    {
                        houseList = sqlDt
                                        .AsEnumerable()
                                        .Select(dataRow => new HouseData
                                        {
                                            house_name = dataRow.Field<string>("house_name"),
                                            address1 = dataRow.Field<string>("address1"),
                                            address2 = dataRow.Field<string>("address2"),
                                            price = dataRow.Field<decimal>("price"),
                                            price_curr = dataRow.Field<string>("price_curr"),
                                        })
         

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0
I use Ola Hallengren's maintenance for all of my customer's, https://ola.hallengren.com/sql-server-backup.html.
Have used it for years, never any real problems -- until now.  For some reason the @CleanupMode and @CleanupTime are not working. The backup step is configured to retain bak files for only 24hrs, and to cleanup the old bak before generating the new.  For some reason, it is not working, and the job keeps failing due to insufficient disk space.

My temporary workaround is below.  I am deleting the largest bak file from disk as a first step in the job, until I get Ola's logic corrected.  Well, it works great as-is, but I've found I need to run it for all subdirectories.

The way it works now is to del the bak file in this path explicitly:
SET @path = 'dir \\backups\servername\dbname\FULL\'

I need it to delete the bak files from all subdirectories within \\backups\servername\

Any help?



SET NOCOUNT ON;

IF OBJECT_ID('tempdb..#files') IS NOT NULL
DROP TABLE #files;
CREATE TABLE #files (Line VARCHAR(512)) 
DECLARE @path VARCHAR(49) 
DECLARE @cmd1 VARCHAR(155)
DECLARE @cmd2 VARCHAR(155)
DECLARE @filename VARCHAR(255)
SET @path = 'dir \\backups\servername\dbname\FULL\'
SET @cmd1 =  @Path+' /A-D  /B' 
--PRINT @cmd1

INSERT #files
EXEC master..xp_cmdshell @cmd1
DELETE #files WHERE Line IS NULL
--SELECT * FROM #files

SET @filename = (SELECT Line FROM #files)
SET @cmd2 = 'del \\backups\servername\dbname\FULL\' + @FileName
--PRINT @cmd2

IF EXISTS(SELECT

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0
I am attempting to register a remote machine on team services with Powershell. When I enter the script on the remote machine and attempt to run it, I get the error below: Cannot add type. The assembly 'System.IO.Compression.FileSystem' could not be found. I have copied the registration script from the Deployment Groups section on team services online.

The server that I am using is windows server 2008 R2. The script is below:

$ErrorActionPreference="Stop";If(-NOT ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] “Administrator”)){ throw "Run command in Administrator PowerShell Prompt"};If(-NOT (Test-Path $env:SystemDrive\'vstsagent')){mkdir $env:SystemDrive\'vstsagent'}; cd $env:SystemDrive\'vstsagent'; for($i=1; $i -lt 100; $i++){$destFolder="A"+$i.ToString();if(-NOT (Test-Path ($destFolder))){mkdir $destFolder;cd $destFolder;break;}}; $agentZip="$PWD\agent.zip";(New-Object Net.WebClient).DownloadFile('https://github.com/Microsoft/vsts-agent/releases/download/v2.116.1/vsts-agent-win7-x64-2.116.1.zip', $agentZip);Add-Type -AssemblyName System.IO.Compression.FileSystem;[System.IO.Compression.ZipFile]::ExtractToDirectory($agentZip, "$PWD");.\config.cmd --deploymentgroup --agent $env:COMPUTERNAME --runasservice --work '_work' --url 'https://aaosprojects.visualstudio.com/' --projectname 'xxxxxxxProjects' --deploymentgroupname "xxxxxxxxxDeploymentGroup" ; Remove-Item $agentZip;
0
I have a problem with my mouse. When i move it to the right it goes down, when i move it to the left it goes up, when i move it up it goes to the right, when i move it down it goes to the left.

i really want to use my mouse can somebody help me.

Im using Armageddon Aquila-X5
0
Get MySQL database support online, now!
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Hello, Experts,

I have an issue with a script where I want the end-user once the app is hit to see the main menu. I have four definitions doing separate tasks (updating, querying or adding in records in a database).

I want my main screen to pop up a list of items for the end users to select. I read that a def main() function is the route to go. Tested it out and I have no luck running it.

def main():
    user_exit =  5
    while True:
            #prints statements that lead the end-user to decide what they would like to do
        print('Welcome to the ROWriter Database applet! What would you like to do?')
        print('')
        print('1) Insert a new store CIM info...')
        print('2) Update an existing store CIM info...')
        print('3) Delete an exisiting store CIM info...')
        print('4) Search for CIM')
        print('5) Exit the application...')
    
            #accepts user input and converts it to a string and stores into a variable
        user_input = int(input('Enter option:'))
        #if user input is equal to the exit variable then the application exits
        if user_input == user_exit:
            break
        elif user_input == 1:
                option_one()
        elif user_input == 2:
                option_two()
        elif user_input == 4:
                option_four()
  
if__name__ == "__main__":
    
    main()  

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0
Is there any way to search for all instances of a string in notepad++ and delete the whole line
on which the string is found?
0
Hi,
I am looking for String Format Method example using various date formats
https://www.javatpoint.com/java-string-format.

I found above link but no example there using the date format though like MMDDYYYY or YYYYMMDD etc to represent date?
please advise
0
Hi,
Is there an example to create list (like what we can get by Gridview) like the following, having Picture file loaded from database?
                <dl id="list_D03_03" onmouseout="mouseOutStyle(this)" onmouseover="mouseOverStyle(this)" class="list rel">
                    <dt class="img rel floatl">
                        <a href="/chushou/3_260353623.htm"  target="_blank">
                            <img width="180" height="135" src="http://img.soufun.com/secondhouse/image/esfnew/search2014/images/loading160_120.gif" src2="http://img11.soufunimg.com/viewimage/agents/2017_05/13/M06/04/17/ChCE4FkWpWiIPlJFAACL93NuA_0AAcAegG1kQ8AAIwP526/220x165c.jpg" onerror="imgiserror(this,'http://img11.soufunimg.com/agents/2017_05/13/M06/04/17/ChCE4FkWpWiIPlJFAACL93NuA_0AAcAegG1kQ8AAIwP526.jpg')" /></a>
                        <p class="txtBg"></p>
                        <p class="txt"><span class="iconImg">10</span></p>
                    </dt>
                    <dd class="info rel floatr">
                        <p class="title"><a href="/chushou/3_260353623.htm"  target="_blank" title="下角</a> 
                            
                        </p>
                        <p class="mt12">
                            2
                            
                            <span class="line">|</span>中
                            <span class='line'>|</span>西
                            <span class='line'>|</span>建
                        </p>
                        

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0
Hi,
Is there any C# example code (or other kind of codes) to be able to show a relevant map part from Baidu, per one given city/place location?
0
Hi

In Java, as per a hashtag or a twitter opportunity,

how can I get a list of users that incorporated / responded to that hashtag / question?

Thanks
0

System Programming

40K

Solutions

19K

Contributors

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.

Top Experts In
System Programming