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  • Multi-reader IPC solution?

    - by gct
    I'm working on a framework in C++ (just for fun for now), that lets the user write plugins that use a standard API to stream data between each other. There's going to be three basic transport mechanisms for the data: files, sockets, and some kind of IPC piping system. The system is set up so that for the non-file transport, each stream can have multiple readers. IE once a server socket it setup, multiple computers can connect and stream the data. I'm a little stuck at the multi-reader IPC system though. All my plugins run in threads so they live in the same address space, so some kind of shared memory system would work fine, I was thinking I'd write my own circular buffer with a write pointer and read pointers chassing it around the buffer, but I have my doubts that I can achieve the same performance as something like linux pipes. I'm curious what people would suggest for a multi-reader solution to something like this? Is the overhead for pipes or domain sockets low enough that I could just open a connection to each reader and issue separate writes to each reader? This is intended to be significant volumes of data (tens of mega-samples/sec), so performance is a must.

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  • Why doesn't the Java Collections API include a Graph implementation?

    - by dvanaria
    I’m currently learning the Java Collections API and feel I have a good understanding of the basics, but I’ve never understood why this standard API doesn’t include a Graph implementation. The three base classes are easily understandable (List, Set, and Map) and all their implementations in the API are mostly straightforward and consistent. Considering how often graphs come up as a potential way to model a given problem, this just doesn’t make sense to me (it’s possible it does exist in the API and I’m not looking in the right place of course). Steve Yegge suggests in one of his blog posts that a programmer should consider graphs first when attacking a problem, and if the problem domain doesn’t fit naturally into this data structure, only then consider the alternative structures. My first guess is that there is no universal way to represent graphs, or that their interfaces may not be generic enough for an API implementation to be useful? But if you strip down a graph to its basic components (vertices and a set of edges that connect some or all of the vertices) and consider the ways that graphs are commonly constructed (methods like addVertex(v) and insertEdge(v1, v2)) it seems that a generic Graph implementation would be possible and useful. Thanks for helping me understand this better.

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  • .net design pattern question

    - by user359562
    Hi. I am trying to understand design pattern problems. I am trying to modify the code like this in winforms and trying to see if any design pattern suits my requirement. Please suggest which is the best design pattern in this scenario. This is very basic code containing 2 tab pages which might have different controls can be added dynamically and read out different files on click of particular tab. To elaborate more... I have written this code to learn and understand design pattern. This is just a scenario where user click on a particular tab which will show dynamic controls generated. public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void tabControl1_SelectedIndexChanged(object sender, EventArgs e) { if (tabControl1.SelectedTab.Name.Equals("tabPage1")) { GeneratedynamicControlsForTab1(); } else if (tabControl1.SelectedTab.Name.Equals("tabPage2")) { GeneratedynamicControlsForTab2(); } } private void GeneratedynamicControlsForTab1() { Label label1 = new Label(); label1.Text = "Label1"; tabPage1.Controls.Add(label1); ReadCSVFile(); } private void GeneratedynamicControlsForTab2() { tabPage1.Controls.Clear(); Label label2 = new Label(); label2.Text = "Label2"; tabPage2.Controls.Add(label2); ReadTextFile(); } private void ReadCSVFile() { } private void ReadTextFile() { } }

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  • How do virtual destructors work?

    - by Prabhu
    Few hours back I was fiddling with a Memory Leak issue and it turned out that I really got some basic stuff about virtual destructors wrong! Let me put explain my class design. class Base { virtual push_elements() {} }; class Derived:public Base { vector<int> x; public: void push_elements(){ for(int i=0;i <5;i++) x.push_back(i); } }; void main() { Base* b = new Derived(); b->push_elements(); delete b; } The bounds checker tool reported a memory leak in the derived class vector. And I figured out that the destructor is not virtual and the derived class destructor is not called. And it surprisingly got fixed when I made the destructor virtual. Isn't the vector deallocated automatically even if the derived class destructor is not called? Is that a quirk in BoundsChecker tool or is my understanding of virtual destructor wrong?

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  • CSS Clearing Floats

    - by Frank
    I'm making more of an effort to separate my html structure from presentation, but sometimes when I look at the complexity of the hacks or workarounds to make things work cross-browser, I'm amazed at huge collective waste of productive hours that are put into this. As I understand it, floats were never created for creating layouts, but because many layouts need a footer, that's how they're often being used. To clear the floats, you can add an empty div that clears both sides (div class="clear"). That is simple and works cross browser, but it adds "non-semantic" html rather than solving the presentation problem within the CSS. I realize this, but after looking at all of the solutions with their benefits and drawbacks, it seems to make more sense to go with the empty div (predictable behavior across browsers), rather than create separate stylesheets, including various css hacks and workarounds, etc. which would also need to change as CSS evolves. Is it o.k. to do this as long as you do understand what you're doing and why you're doing it? Or is it better to find the CSS workarounds, hacks and separate structure from presentation at all costs, even when the CSS presentation tools provided are not evolved to the point where they can handle such basic layout issues?

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  • Run Javascript on the body of a Gmail message

    - by saturn
    I want to display LaTeX math in the gmail messages that I receive, so that for example $\mathbb P^2$ would show as a nice formula. Now, there are several Javascripts available (for example, this one, or MathJax which would do the job, I just need to call them at the right time to manipulate the gmail message. I know that this is possible to do in "basic HTML" and "print" views. Is it possible to do in the standard Gmail view? I tried to insert a call to the javascript right before the "canvas_frame" iframe, but that did not work. My suspicion is that manipulating a Gmail message by any Javascript would be a major security flaw (think of all the malicious links one could insert) and that Google does everything to prevent this. And so the answer to my question is probably 'no'. Am I right in this? Of course, it would be very easy for Google to implement viewing of LaTeX and MathML math simply by using MathJax on their servers. I made the corresponding Gmail Lab request, but no answer, and no interest from Google apparently. So, again: is this possible to do without Google's cooperation, on the client side?

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  • How can I format Custom Data and display in autocomplete when source is an DB

    - by Andres Scarpone
    so I'm trying to get some info in the auto-complete widget like it's shown in the JQuery UI demo Demo, the only problem is they use a variable that they fill with the data they want to show, I instead want to access the data and the different description and stuff using a Data Base in MySQL, for this I have changed the source to use another php page that looks up the info. here is the code for the Auto-complete, I really don't understand the methods so I haven't changed it from the basic search. This is the JS: $(document).ready((function(){ $( "#completa" ).autocomplete({ source: "buscar.php", minLength: 1, focus: function (event, ui){ $("#completa").val(ui.item.val); return false; }; })); This is what I have in buscar.php: <?php $conec = mysql_connect(localhost, root, admin); if(!$conec) { die(mysql_error()); } else { $bd = mysql_select_db("ve_test",$conec ); if(!$bd) { die(mysql_error()); } } $termino = trim(strip_tags($_GET['term']));//Obtener el termino que envia el autocompletar $qstring = "SELECT name, descripcion FROM VE_table WHERE name LIKE '%".$termino."%'"; $result = mysql_query($qstring);//Solicitud a la Base de Datos while ($row = mysql_fetch_array($result,MYSQL_ASSOC))//Realizar un LOOP sobre los valores obtenidos { $row['value']=htmlentities(stripslashes($row['name'])); $row_set[] = $row;//build an array } echo json_encode($row_set);//Enviar los datos al autocompletar en codificacion JSON, Altamente Necesario. ?

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  • How do I create rows with alternating colors for a UITableView on iPhone?

    - by Mat
    Hi all, i would to have alternate 2 colors of rows, like the first black, the second white, the third black, etc, etc... my approach is like a basic exercise of programming to calculate if a number is odd number or not: - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; cell = ((MainCell*)[tableView dequeueReusableCellWithIdentifier:CellIdentifier]); if (cell==nil) { NSArray *topLevelObjects=[[NSBundle mainBundle] loadNibNamed:@"MainCell" owner:self options:nil]; for (id currentObject in topLevelObjects){ if ([currentObject isKindOfClass:[UITableViewCell class]]){ if ((indexPath.row % 2)==0) { [cell.contentView setBackgroundColor:[UIColor purpleColor]]; }else{ [cell.contentView setBackgroundColor:[UIColor whiteColor]]; } cell = (MainCell *) currentObject; break; } } }else { AsyncImageView* oldImage = (AsyncImageView*) [cell.contentView viewWithTag:999]; [oldImage removeFromSuperview]; }return cell; The problem is that when i do a rapid scroll, the background of cells become like the last 2 cell black, the first 2 cell white or something like this, but if i scroll slow works fine. I think the problem is the cache of reusableCell. Any ideas? TIA

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  • What is the best cross-platform language for desktop applications? (Java, Adobe Air, Flex, Silverlight??, Anything Else)

    - by Sootah
    My business partner needs a desktop application programmed, and it needs to be cross-platform as he wants Mac owners (OS X) to be able to run it as well. This, of course, is a bit of a problem for me as I program in PHP for my web projects and exclusively in C# (formerly used Visual Basic) for my desktop apps. I've been using (and love) NetBeans for my PHP stuff, and love Visual Studio just as much; they're both excellent IDEs. With this in mind, I'd like to find a language and IDE that's as similar to Visual Studio as possible (or at least something that makes development as easy as it does) for my cross-platform application development. In fact, if there is a language I can use with VS I'd be extremely happy. I realize that NetBeans has a Java Desktop App IDE, but have been having problems with it (my question in regards to that issue is here. I am also not sure that I really want to learn and use Java if there is a better, easier option out there. Obviously, the first language that came to mind that I can use cross-platform was Java, but I've also heard of people using Adobe Air, as well as Flex being used. I've never programmed in any of those languages, and as such have no frame of reference from which I can decide which would be best for me. I'm also not sure what other options there may be for me; perhaps there's another language I can use that'd be better than the three options I've already provided. (Can you make desktop apps with Silverlight? If so, did MS make an interpreter that will get them to work on OS X?) I like the syntax of C# quite a bit, and the Visual Studio IDE makes it extremely easy to make my apps with. As such, I'd like to find something that'll work as well for me with the cross-platform shatner as C# and its IDE does with my Windows apps. Thanks in advance for your help/opinions!

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  • Looking for Opinions and Sugestions on my Website. (General Question)

    - by MrEnder
    I am looking for general opinions and suggestions about the site in whole. Its ok I don't mind hearing where I went wrong on anything. I'm still learning. All tips and pointers on any subject relating are highly welcome. If you are going to make a suggestion and post a snippet or code please explain how it works in detail. The site was design as a interface to display the labs I have to do in my college (the labs are all basic things that I'm way beyond). So I decided to take it all to the next level with this. The link is http://opentech.durhamcollege.ca/~intn2201/brittains/labs/ It is 100% designed by me with the exception of the icons. (I could not think of anything better to draw) There is no specific area of the site I want suggestions or opinions on this is a general question. You may answer about the site in whole or an area of the coding just please specify. If you have any questions related to my site or code you may ask them as well. Thank you for your time and any comments Shelby

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  • starting a windows executable via batch script, exe not in Program Files

    - by Anthony
    This is probably batch scripting 101, but I can't find any clear explanation/documentation on why this is happening or if my workaround is actually the solution. So basically any terminology or links to good sources is really appreciated. So I have a program I want to execute via batch script (along with several other programs). It's the only one where the exe is not in a Program Files folder. I can get it to start like this: C:\WeirdProgram\WeirdProgramModule\weirdmodule.exe But I get an error along the lines of: Run-time Error '3024': Could not find file C:\Users\MyUserName\Desktop\ModuleSettings.mdb So it seems that the program is looking for its settings files from the same location that the batch script starts up. Given that I finally got everything to work by doing the following: cd C:\WeirdProgram\WeirdProgramModule\ weirdmodule.exe That works fine, and it's not the end of the world to have to go this route (just one extra line), but I've convinced myself that I'm doing something wrong based on lack of basic understanding. Anybody know or can point me to why it works this way? Oh, and doing the following: start "C:\WeirdProgram\WeirdProgramModule\weirdmodule.exe" doesn't do anything at all. Thanks,

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  • C++/Win32 : XP Visual Styles - no controls are showing up?

    - by mrl33t
    Okay, so i'm pretty new to C++ & the Windows API and i'm just writing a small application. I wanted my application to make use of visual styles in both XP, Vista and Windows 7 so I added this line to the top of my code: #pragma comment(linker,"\"/manifestdependency:type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"") It seemed to work perfectly on my Windows 7 machine and also Vista machine. But when I tried the application on XP the application wouldn't load any controls (e.g. buttons, labels etc.) - not even messageboxes would display. This image shows a small test application which i've just put together to demonstrate what i'm trying to explain: http://img704.imageshack.us/img704/2250/myapp.png In this test application i'm not using any particularly fancy or complicated code. I've effectively just taken the most basic sample code from the MSDN Library (http://msdn.microsoft.com/en-us/library/ff381409.aspx) and added a section to the WM_CREATE message to create a button: MyBtn = CreateWindow(L"Button", L"My Button", BS_PUSHBUTTON | WS_CHILD | WS_VISIBLE, 25, 25, 100, 30, hWnd, NULL, hInst, 0); But I just can't figure out what's going on and why its not working. Any ideas guys? Thank you in advanced. (By the way the application works in XP if i remove the manifest section from the top - obviously without visual styles though. I should also probably mention that the app was built using Visual C++ 2010 Express on a Windows 7 machine - if that makes a difference?)

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  • Best practice accessing an array set within a class

    - by user350599
    I have created a basic class for a customer. I haven't done this before and want to know the best way to access the data. Should I have a get() method for every field in the customer array or should I simply pass the customer array back and access with the page. i.e. Just return the array class Customer { protected $id; protected $customer; public function __construct($customer_id) { $this->id = $customer_id; $this->set_customer(); } protected function set_customer() { $query = mysql_query("SELECT * FROM customer WHERE id = '$this->id'"); $this->customer = mysql_fetch_row($query); } public function get_customer() { return $this->customer; } } versus create a method for each item in the array class Customer { protected $id; protected $customer; public function __construct($customer_id) { $this->id = $customer_id; $this->set_customer(); } protected function set_customer() { $query = mysql_query("SELECT * FROM customer WHERE id = '$this->id'"); $this->customer = mysql_fetch_row($query); } public function get_customer_name() { return $this->customer->customer_name; } ... ... } versus option 3 based on Tobias' feedback: (not sure if syntax is correct) class Customer { protected $id; protected $customer; public function __construct($customer_id) { $this->id = $customer_id; return $this->set_customer(); } protected function set_customer() { $query = mysql_query("SELECT * FROM customer WHERE id = '$this->id'"); return mysql_fetch_row($query); } }

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  • Firefox proxy dilemma

    - by Mike L.
    Any idea why when using system proxy settings in firefox, it can not accept a proxy such as: user:[email protected]:port ??? IE will allow and connect to a proxy in this format. Not only does firefox not work, but it does not prompt for the password, nor attempt to make a connection to the proxy. Basically get a "proxy server not found" error. Anybody know a way around this? I am working on a proxy switching program for IE & Firefox, and I would like to use system-wide proxy settings. If I just store the server:port combination, firefox prompts for the password, as well as IE. Then they can be cached and it will not ask again. Maybe my only option is to programmatically cache the user/pass? Anybody know a way to do this? I am pretty sure IE stores them at HTTP basic authentication passwords and I can add them with AddCredential. After saving a password for a proxy in firefox, it shows up in saved passwords in a format like "moz-proxy://server:port" anybody know how to programmatically add a saved password to firefox? Thanks

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  • How can I lookup data about a book from its barcode number?

    - by Joel Spolsky
    I'm building the world's simplest library application. All I want to be able to do is scan in a book's UPC (barcode) using a typical scanner (which just types the numbers of the barcode into a field) and then use it to look up data about the book... at a minimum, title, author, year published, and either the Dewey Decimal or Library of Congress catalog number. The goal is to print out a tiny sticker ("spine label") with the card catalog number that I can stick on the spine of the book, and then I can sort the books by card catalog number on the shelves in our company library. That way books on similar subjects will tend to be near each other, for example, if you know you're looking for a book about accounting, all you have to do is find SOME book about accounting and you'll see the other half dozen that we have right next to it which makes it convenient to browse the library. There seem to be lots of web APIs to do this, including Amazon and the Library of Congress. But those are all extremely confusing to me. What I really just want is a single higher level function that takes a UPC barcode number and returns some basic data about the book.

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  • strcmp() but with 0-9 AFTER A-Z? (C/C++)

    - by Aaron
    For reasons I completely disagree with but "The Powers (of Anti-Usability) That Be" continue to decree despite my objections, I have a sorting routine which does basic strcmp() compares to sort by its name. It works great; it's hard to get that one wrong. However, at the 11th hour, it's been decided that entries which begin with a number should come AFTER entries which begin with a letter, contrary to the ASCII ordering. They cite the EBCDIC standard has numbers following letters so the prior assumption isn't a universal truth, and I have no power to win this argument... but I digress. Therein lies my problem. I've replaced all appropriate references to strcmp with a new function call nonstd_strcmp, and now need to implement the modifications to accomplish the sort change. I've used a FreeBSD source as my base: http://freebsd.active-venture.com/FreeBSD-srctree/newsrc/libkern/strncmp.c.html if (n == 0) return (0); do { if (*s1 != *s2++) return (*(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1)); if (*s1++ == 0) break; } while (--n != 0); return (0); I guess I might need to take some time away to really think about how it should be done, but I'm sure I'm not the only one who's experienced the brain-deadness of just-before-release spec changes.

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  • How to format individual DropDownlist Items (color, etc.) during onDataBinding event

    - by LesterDove
    Hi, I have a basic DropDownList bound to a ObjectDataSource: <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" DataSourceID="objDataSource1" DataTextField="FieldName" DataValueField="FieldID" /> The DataTable from which it receives the DataTextField and DataValueField values also returns some other interesting information about the records. Say Active = Y/N for simplicity's sake. What I'd like to do is to set the background-color property of the DropDownList Item based on that Active field in the DataSource results. Further, I'd like to do this "in the same pass" as when the DropDownList is bound to the data. So my guess is that it has to happen during OnDataBinding. Things I already know/tried: I could go back and loop through the DropDownList items later. But it would involve embedding loops and re-visiting the DataTable rows and it just seems inefficient int row; for (row = 0; row < DropDownList1.Items.Count - 1; row++) { [[if this row = that data row]] DropDownList1.Items[row].[[DoStuffHere, etc.]] } We already do stuff like this with the GridView OnRowDataBound event, by accessing the GridViewRowEventArgs e. What I seem to be missing is an "OnDropDownListItemBound" event, so to speak. Hope I've been clear and concise. Seems as though it should be easy...

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  • Read/Write/Find/Replace huge csv file

    - by notapipe
    I have a huge (4,5 GB) csv file.. I need to perform basic cut and paste, replace operations for some columns.. the data is pretty well organized.. the only problem is I cannot play with it with Excel because of the size (2000 rows, 550000 columns). here is some part of the data: ID,Affection,Sex,DRB1_1,DRB1_2,SENum,SEStatus,AntiCCP,RFUW,rs3094315,rs12562034,rs3934834,rs9442372,rs3737728 D0024949,0,F,0101,0401,SS,yes,?,?,A_A,A_A,G_G,G_G D0024302,0,F,0101,7,SN,yes,?,?,A_A,G_G,A_G,?_? D0023151,0,F,0101,11,SN,yes,?,?,A_A,G_G,G_G,G_G I need to remove 4th, 5th, 6th, 7th, 8th and 9th columns; I need to find every _ character from column 10 onwards and replace it with a space ( ) character; I need to replace every ? with zero (0); I need to replace every comma with a tab; I need to remove first row (that has column names; I need to replace every 0 with 1, every 1 with 2 and every ? with 0 in 2nd column; I need to replace F with 2, M with 1 and ? with 0 in 3rd column; so that in the resulting file the output reads: D0024949 1 2 A A A A G G G G D0024302 1 2 A A G G A G 0 0 D0023151 1 2 A A G G G G G G (both input and output should read one line per row, ne extra blank row) Is there a memory efficient way of doing that with java(and I need a code to do that) or a usable tool for playing with this large data so that I can easily apply Excel functionality..

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  • Program to find the result of primitive recursive functions

    - by alphomega
    I'm writing a program to solve the result of primitive recursive functions: 1 --Basic functions------------------------------ 2 3 --Zero function 4 z :: Int -> Int 5 z = \_ -> 0 6 7 --Successor function 8 s :: Int -> Int 9 s = \x -> (x + 1) 10 11 --Identity/Projection function generator 12 idnm :: Int -> Int -> ([Int] -> Int) 13 idnm n m = \(x:xs) -> ((x:xs) !! (m-1)) 14 15 --Constructors-------------------------------- 16 17 --Composition constructor 18 cn :: ([Int] -> Int) -> [([Int] -> Int)] -> ([Int] -> Int) 19 cn f [] = \(x:xs) -> f 20 cn f (g:gs) = \(x:xs) -> (cn (f (g (x:xs))) gs) these functions and constructors are defined here: http://en.wikipedia.org/wiki/Primitive_recursive_function The issue is with my attempt to create the compositon constructor, cn. When it gets to the base case, f is no longer a partial application, but a result of the function. Yet the function expects a function as the first argument. How can I deal with this problem? Thanks.

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  • OpenSocial create activity from submit click

    - by russp
    Hi I'm "playing with OpsnSocial" and think I get a lot of it (well thanks to Googles' bits) but one question if I may. Creating an activity Lets say I have a form like this (simple) <form> <input type="text" name="" id="testinput" value=""/> <input type="submit" name="" id="" value=""/> </form> And I want to post the value of the text field (and or a message i.e "just posted" to the "users" activity. Do I use a function like this? function createActivity() { if (viewer) { var activity = opensocial.newActivity({ title: viewer.getDisplayName() + ' VALUE FROM FORM '}); opensocial.requestCreateActivity(activity, "HIGH", function() { setTimeout(initAllData,1000); }); } }; If so, how do I pass the text field value to it - is it something like this? var testinput = document.getElementById("testinput"); so the function may look like function createActivity() { if (viewer) { var activity = opensocial.newActivity({ title: viewer.getDisplayName() + testinput }); opensocial.requestCreateActivity(activity, "HIGH", function() { setTimeout(initAllData,1000); }); } }; And how do I trigger the function by using the submit button. In my basic JQuery I would use $('#submitID').submit(function(){ 'bits in here '}); Is at "simple as that i.e. use the createActivity function and it will use the OS framework to "post" to the activity.xml

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  • Finding missing files by checksum

    - by grw
    Hi there, I'm doing a large data migration between two file systems (let's call them F1 and F2) on a Linux system which will necessarily involve copying the data verbatim into a differently-structured hierarchy on F2 and changing the file names. I'd like to write a script to generate a list of files which are in F1 but not in F2, i.e. the ones which weren't copied by the migration script into the new hierarchy, so that I can go back and migrate them manually. Unfortunately for reasons not worth going into, the migration script can't be modified to list files that it doesn't migrate. My question differs from this previously answered one because of the fact that I cannot rely on filenames as a comparison. I know the basic outline of the process would be: Generate a list of checksums for all files, recursing through F1 Do the same for F2 Compare the lists and generate a negative intersection of the checksums, ignoring the file names, to find files which are in F1 but not in F2. I'm kind of stuck getting past that stage, so I'd appreciate any pointers on which tools to use. I think I need to use the 'comm' command to compare the list of file checksums, but since md5sum, sha512sum and the like put the file name next to the checksum, I can't see a way to get it to bring me a useful comparison. Maybe awk is the way to go? I'm using Red Hat Enterprise Linux 5.x. Thanks.

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  • Would an immutable keyword in Java be a good idea?

    - by berry120
    Generally speaking, the more I use immutable objects in Java the more I'm thinking they're a great idea. They've got lots of advantages from automatically being thread-safe to not needing to worry about cloning or copy constructors. This has got me thinking, would an "immutable" keyword go amiss? Obviously there's the disadvantages with adding another reserved word to the language, and I doubt it will actually happen primarily for the above reason - but ignoring that I can't really see many disadvantages. At present great care has to be taken to make sure objects are immutable, and even then a dodgy javadoc comment claiming a component object is immutable when it's in fact not can wreck the whole thing. There's also the argument that even basic objects like string aren't truly immutable because they're easily vunerable to reflection attacks. If we had an immutable keyword the compiler could surely recursively check and give an iron clad guarantee that all instances of a class were immutable, something that can't presently be done. Especially with concurrency becoming more and more used, I personally think it'd be good to add a keyword to this effect. But are there any disadvantages or implementation details I'm missing that makes this a bad idea?

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  • Firefox proxy delima

    - by Mike L.
    Any idea why when using system proxy settings in firefox, it can not accept a proxy such as: user:[email protected]:port ??? IE will allow and connect to a proxy in this format. Not only does firefox not work, but it does not prompt for the password, nor attempt to make a connection to the proxy. Basically get a "proxy server not found" error. Anybody know a way around this? I am working on a proxy switching program for IE & Firefox, and I would like to use system-wide proxy settings. If I just store the server:port combination, firefox prompts for the password, as well as IE. Then they can be cached and it will not ask again. Maybe my only option is to programmatically cache the user/pass? Anybody know a way to do this? I am pretty sure IE stores them at HTTP basic authentication passwords and I can add them with AddCredential. After saving a password for a proxy in firefox, it shows up in saved passwords in a format like "moz-proxy://server:port" anybody know how to programmatically add a saved password to firefox? Thanks

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  • Is There a Better Way to Feed Different Parameters into Functions with If-Statements?

    - by FlowofSoul
    I've been teaching myself Python for a little while now, and I've never programmed before. I just wrote a basic backup program that writes out the progress of each individual file while it is copying. I wrote a function that determines buffer size so that smaller files are copied with a smaller buffer, and bigger files are copied with a bigger buffer. The way I have the code set up now doesn't seem very efficient, as there is an if loop that then leads to another if loops, creating four options, and they all just call the same function with different parameters. import os import sys def smartcopy(filestocopy, dest_path, show_progress = False): """Determines what buffer size to use with copy() Setting show_progress to True calls back display_progress()""" #filestocopy is a list of dictionaries for the files needed to be copied #dictionaries are used as the fullpath, st_mtime, and size are needed if len(filestocopy.keys()) == 0: return None #Determines average file size for which buffer to use average_size = 0 for key in filestocopy.keys(): average_size += int(filestocopy[key]['size']) average_size = average_size/len(filestocopy.keys()) #Smaller buffer for smaller files if average_size < 1024*10000: #Buffer sizes determined by informal tests on my laptop if show_progress: for key in filestocopy.keys(): #dest_path+key is the destination path, as the key is the relative path #and the dest_path is the top level folder copy(filestocopy[key]['fullpath'], dest_path+key, callback = lambda pos, total: display_progress(pos, total, key)) else: for key in filestocopy.keys(): copy(filestocopy[key]['fullpath'], dest_path+key, callback = None) #Bigger buffer for bigger files else: if show_progress: for key in filestocopy.keys(): copy(filestocopy[key]['fullpath'], dest_path+key, 1024*2600, callback = lambda pos, total: display_progress(pos, total, key)) else: for key in filestocopy.keys(): copy(filestocopy[key]['fullpath'], dest_path+key, 1024*2600) def display_progress(pos, total, filename): percent = round(float(pos)/float(total)*100,2) if percent <= 100: sys.stdout.write(filename + ' - ' + str(percent)+'% \r') else: percent = 100 sys.stdout.write(filename + ' - Completed \n') Is there a better way to accomplish what I'm doing? Sorry if the code is commented poorly or hard to follow. I didn't want to ask someone to read through all 120 lines of my poorly written code, so I just isolated the two functions. Thanks for any help.

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  • Why Does My Vector<PEVENTLOGRECORD> Mysteriously Get Cleared?

    - by Eric
    Hello everyone, I am making a program that reads and stores data from Windows EventLog files (.evt) in C++. I am using the calls OpenBackupEventLog(ServerName, FileName) and ReadEventLog(...). Also using this: PEVENTLOGRECORD Anyway, without supplying all of the code, here is the basic idea: 1. I get a handle to the .evt file using OpenBackupEventLog() and passing in a file name. 2. I then use ReadEventLog() to fill up a buffer with an unknown number of EventLog messages. 3. I traverse through the buffer and add each message to a vector 4. I keep filling up buffers (repeat steps 2 and 3) until I reach the end of the file. Here is my code for filling the vector: vector<PEVENTLOGRECORD> allRecords; while(_status == ERROR_SUCCESS) { if(!ReadEventLog(...)) CheckStatus(); else FillVectorFromBuffer(allRecords) } // Function FillVectorFromBuffer FillVectorFromBuffer(vector(PEVENTLOGRECORD) &allRecords) { int bytesExamined = 0; PBYTE pRecord = (PBYTE)_lpBuffer; // This is one of the params in ReadEventLog() while(bytesExamined < _pnBytesRead) // Another param from ReadEventLog { PEVENTLOGRECORD currentRecord = (PEVENTLOGRECORD)(pRecord); allRecords.push_back(currentRecord); pRecord += currentRecord->Length; bytesExamined += currentRecord->Length; } } Anyway, whenever I run this, it will get all the EventLogs in the file, and the vector will have everything I want it to. But as soon as this line: if(!ReadEventLog()) gets called and returns true (aka ReadEventLog() returns false), then every field in my vector gets set to zero. The vector will still contain the correct number of elements, it's just that all of the fields in the PEVENTLOGRECORD struct are now zero. Anyone with better debugging experience have any ideas? Thanks.

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