Search Results

Search found 9275 results on 371 pages for 'condition variables'.

Page 324/371 | < Previous Page | 320 321 322 323 324 325 326 327 328 329 330 331  | Next Page >

  • C++ struct, public data members and inheritance

    - by Marius
    Is it ok to have public data members in a C++ class/struct in certain particular situations? How would that go along with inheritance? I've read opinions on the matter, some stated already here http://stackoverflow.com/questions/952907/practices-on-when-to-implement-accessors-on-private-member-variables-rather-than http://stackoverflow.com/questions/670958/accessors-vs-public-members or in books/articles (Stroustrup, Meyers) but I'm still a little bit in the shade. I have some configuration blocks that I read from a file (integers, bools, floats) and I need to place them into a structure for later use. I don't want to expose these externally just use them inside another class (I actually do want to pass these config parameters to another class but don't want to expose them through a public API). The fact is that I have many such config parameters (15 or so) and writing getters and setters seems an unnecessary overhead. Also I have more than one configuration block and these are sharing some of the parameters. Making a struct with all the data members public and then subclassing does not feel right. What's the best way to tackle that situation? Does making a big struct to cover all parameters provide an acceptable compromise (I would have to leave some of these set to their default values for blocks that do not use them)?

    Read the article

  • Inline function v. Macro in C -- What's the Overhead (Memory/Speed)?

    - by Jason R. Mick
    I searched Stack Overflow for the pros/cons of function-like macros v. inline functions. I found the following discussion: Pros and Cons of Different macro function / inline methods in C ...but it didn't answer my primary burning question. Namely, what is the overhead in c of using a macro function (with variables, possibly other function calls) v. an inline function, in terms of memory usage and execution speed? Are there any compiler-dependent differences in overhead? I have both icc and gcc at my disposal. My code snippet I'm modularizing is: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = AttractiveTerm * AttractiveTerm; EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); My reason for turning it into an inline function/macro is so I can drop it into a c file and then conditionally compile other similar, but slightly different functions/macros. e.g.: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = pow(SigmaSquared/RadialDistanceSquared,9); EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); (note the difference in the second line...) This function is a central one to my code and gets called thousands of times per step in my program and my program performs millions of steps. Thus I want to have the LEAST overhead possible, hence why I'm wasting time worrying about the overhead of inlining v. transforming the code into a macro. Based on the prior discussion I already realize other pros/cons (type independence and resulting errors from that) of macros... but what I want to know most, and don't currently know is the PERFORMANCE. I know some of you C veterans will have some great insight for me!!

    Read the article

  • Image jQuery scroller in a container. (like facebook cropper) can't get values of position.

    - by Stefan
    Hey all. Having a reallllll mind pain. I have a php image uploader which is all good and sotring the file and the jquery ajax is returning the image in an ammended html div with a div set up like this: #crop-holder { width:80px; height:80px; margin:10px 10px 20px 10px; border:1px #c0c0c0 solid; overflow:hidden; cursor:move; } The image is viewing fine and I am using the jquery scrollview plugin: http://code.google.com/p/jquery-scrollview/ I have tried adding a few lines to the plugin to store variables of scrollTop and Left and then replacing two hidden input values with x and y in my page. And then on the returned ajax html in the div I am trying to on a button click (for example) retrieve the values of the two hidden inputs.... Heres what i added to the plugin (i'm no js expert!): .mouseout(function(){ var _m = this.m; var lasty = _m.scrollTop(); getElementById("ycord").value = lasty; var lastx = _m.scrollLeft(); getElementById("xcord").value = lastx; self.stopgrab(); }) Still no luck!! How can I get the scrollTop and scrollLeft and successfully prepare them for sending onto another php script!? Thanks:) stefpretty

    Read the article

  • Powershell: splatting after passing hashtable by reference

    - by user1815871
    Powershell newbie ... I recently learned about splatting — very useful. I ran into a snag when I passed a hash table by reference to a function for splatting purposes. (For brevity's sake — a silly example.) Function AllMyChildren { param ( [ref]$ReferenceToHash } get-childitem @ReferenceToHash.Value # etc.etc. } $MyHash = @{ 'path' = '*' 'include' = '*.ps1' 'name' = $null } AllMyChildren ([ref]$MyHash) Result: an error ("Splatted variables cannot be used as part of a property or array expression. Assign the result of the expression to a temporary variable then splat the temporary variable instead."). Tried this afterward: $newVariable = $ReferenceToHash.Value get-childitem @NewVariable That did work and seemed right per the error message. But: is it the preferred syntax in a case like this? (An oh, look, it actually worked solution isn't always a best practice. My approach here strikes me as "Perl-minded" and perhaps in Powershell passing by value is better, though I don't yet know the syntax for it w.r.t. a hash table.)

    Read the article

  • Looping through covariates in regression using R

    - by Kyle Peyton
    I'm trying to run 96 regressions and save the results as 96 different objects. To complicate things, I want the subscript on one of the covariates in the model to also change 96 times. I've almost solved the problem but I've unfortunately hit a wall. The code so far is, for(i in 1:96){ assign(paste("z.out", i,sep=""), lm(rMonExp_EGM~ TE_i+ Month2+Month3+Month4+Month5+Month6+Month7+Month8+Month9+ Month10+Month11+Month12+Yrs_minus_2004 + as.factor(LGA),data=Pokies)) } This works on the object creation side (e.g. I have z.out1 - z.out96) but I can't seem to get the subscript on the covariate to change as well. I have 96 variables called TE_1, TE_2 ... TE_96 in the dataset. As such, the subscript on TE_, the "i" needs to change to correspond to each of the objects I create. That is, z.out1 should hold the results from this model: z.out1 <- lm(rMonExp_EGM~ TE_1 + Month2+Month3+Month4+Month5+Month6+Month7+Month8+Month9+ Month10+Month11+Month12+Yrs_minus_2004 + as.factor(LGA),data=Pokies) And z.out96 should be: z.out96 <- lm(rMonExp_EGM~ TE_96+ Month2+Month3+Month4+Month5+Month6+Month7+Month8+Month9+ Month10+Month11+Month12+Yrs_minus_2004 + as.factor(LGA),data=Pokies) Hopefully this makes sense. I'm grateful for any tips/advice. cheers, kyle

    Read the article

  • Passing a outside variable into a <asp:sqldatasource> tag. ASP.NET 2.0

    - by MadMAxJr
    I'm designing some VB based ASP.NET 2.0, and I am trying to make more use of the various ASP tags that visual studio provides, rather than hand writing everything in the code-behind. I want to pass in an outside variable from the Session to identify who the user is for the query. <asp:sqldatasource id="DataStores" runat="server" connectionstring="<%$ ConnectionStrings:MY_CONNECTION %>" providername="<%$ ConnectionStrings:MY_CONNECTION.ProviderName %>" selectcommand="SELECT THING1, THING2 FROM DATA_TABLE WHERE (THING2 IN (SELECT THING2 FROM RELATED_DATA_TABLE WHERE (USERNAME = @user)))" onselecting="Data_Stores_Selecting"> <SelectParameters> <asp:parameter name="user" defaultvalue ="" /> </SelectParameters> </asp:sqldatasource> And on my code behind I have: Protected Sub Data_Stores_Selecting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.SqlDataSourceSelectingEventArgs) Handles Data_Stores.Selecting e.Command.Parameters("user").Value = Session("userid") End Sub Oracle squaks at me with ORA-01036, illegal variable name. Am I declaring the variable wrong in the query? I thought external variables share the same name with a @ prefixed. from what I understand, this should be placing the value I want into the query when it executes the select. EDIT: Okay, thanks for the advice so far, first error was corrected, I need to use : and not @ for the variable declaration in the query. Now it generates an ORA-01745 invalid host/bind variable name. EDIT AGAIN: Okay, looks like user was a reserved word. It works now! Thanks for other points of view on this one. I hadn't thought of that approach.

    Read the article

  • Microsoft JScript runtime error Object doesn't support this property or method

    - by Darxval
    So i am trying to call this function in my javascript but it gives me the error of "Microsoft JScript runtime error Object doesn't support this property or method" and i cant figure out why. It is occuring when trying to call hmacObj.getHMAC. This is from the jsSHA website: http://jssha.sourceforge.net/ to use the hmac-sha1 algorithm encryption. Thank you! hmacObj = new jsSHA(signature_base_string,"HEX"); signature = hmacObj.getHMAC("hgkghk","HEX","SHA-1","HEX"); Above this i have copied the code from sha.js snippet: function jsSHA(srcString, inputFormat) { /* * Configurable variables. Defaults typically work */ jsSHA.charSize = 8; // Number of Bits Per character (8 for ASCII, 16 for Unicode) jsSHA.b64pad = ""; // base-64 pad character. "=" for strict RFC compliance jsSHA.hexCase = 0; // hex output format. 0 - lowercase; 1 - uppercase var sha1 = null; var sha224 = null; The function it is calling (inside of the jsSHA function) (snippet) this.getHMAC = function (key, inputFormat, variant, outputFormat) { var formatFunc = null; var keyToUse = null; var blockByteSize = null; var blockBitSize = null; var keyWithIPad = []; var keyWithOPad = []; var lastArrayIndex = null; var retVal = null; var keyBinLen = null; var hashBitSize = null; // Validate the output format selection switch (outputFormat) { case "HEX": formatFunc = binb2hex; break; case "B64": formatFunc = binb2b64; break; default: return "FORMAT NOT RECOGNIZED"; }

    Read the article

  • Setting Up a Wordpress Function in theme's function.php File

    - by user1609391
    I am trying to create the below function in my theme's function.php file and call it from my taxonomy.php file via query_brands_geo('dealers', 'publish', '1', $taxtype, $geo, $brands); all variables are set in taxonomy.php. The below query works perfect if I put it directly in my taxonomy.php file. What am I missing to make this work as a function? As a function I get this error statement for argument repeated for 2-6: Warning: Missing argument 2 for query_brands_geo() function query_brands_geo($posttype, $poststatus, $paidvalue, $taxtype, $geo, $brands) { /* Custom Query for a brand/geo combination to display dealers with a certain brand and geography */ //Query only for brands/geography combo and paid dealers $wp_query = new WP_Query(); $args = array( 'post_type' => '$posttype', 'post_status' => array($poststatus), 'orderby' => 'rand', 'posts_per_page' => 30, 'meta_query' => array( array( 'key' => 'wpcf-paid', 'value' => array($paidvalue), 'compare' => 'IN', ) ), 'tax_query' => array( 'relation' => 'AND', array( 'taxonomy' => $taxtype, 'field' => 'slug', 'terms' => $geo ), array( 'taxonomy' => 'brands', 'field' => 'slug', 'terms' => $brands ) ) ); $wp_query->query($args); } add_action( 'after_setup_theme', 'query_brands_geo' );

    Read the article

  • KO3: How to deal with stylesheets and scriptfiles

    - by Svish
    I'm using Kohana 3 and it's template controller. My main site template controller currently looks something like this: <?php defined('SYSPATH') or die('No direct script access.'); abstract class Controller_SiteTemplate extends Controller_Template { public function before() { parent::before(); // Initialize default template variables $this->template->styles = Kohana::config('site.styles'); $this->template->scripts = Kohana::config('site.scripts'); $this->template->title = ''; $this->template->content = ''; } } And then in my template view I do: <?php # Styles foreach($styles as $file => $media) echo HTML::style($file, array('media' => $media)).PHP_EOL ?> <?php # Scripts foreach($scripts as $file) echo HTML::script($file).PHP_EOL ?> This works alright. The problem is that it requires the style- and script files to be added in the controller, which shouldn't really have to care about those. It also makes it a hassle if the views are done by someone else than me since they would have to fool around with the controller just to add a new stylesheet or a new script file. How can this be done in a better way? Just to clearify, what I am wondering is how to deal with page specific stylesheets and scripts. The default and site-wide ones I have no problem with fetching from a config file or just put directly in the template view. My issue is how to add custom ones for specific pages in a good way.

    Read the article

  • unexpected behaviour of object stored in web service Session

    - by draconis
    Hi. I'm using Session variables inside a web service to maintain state between successive method calls by an external application called QBWC. I set this up by decorating my web service methods with this attribute: [WebMethod(EnableSession = true)] I'm using the Session variable to store an instance of a custom object called QueueManager. The QueueManager has a property called ChangeQueue which looks like this: [Serializable] public class QueueManager { ... public Queue<QBChange> ChangeQueue { get; set; } ... where QBChange is a custom business object belonging to my web service. Now, every time I get a call to a method in my web service, I use this code to retrieve my QueueManager object and access my queue: QueueManager qm = (QueueManager)Session[ticket]; then I remove an object from the queue, using qm.dequeue() and then I save the modified query manager object (modified because it contains one less object in the queue) back to the Session variable, like so: Session[ticket] = qm; ready for the next web service method call using the same ticket. Now here's the thing: if I comment out this last line //Session[ticket] = qm; , then the web service behaves exactly the same way, reducing the size of the queue between method calls. Now why is that? The web service seems to be updating a class contained in serialized form in a Session variable without being asked to. Why would it do that? When I deserialize my Queuemanager object, does the qm variable hold a reference to the serialized object inside the Session[ticket] variable?? This seems very unlikely.

    Read the article

  • Is there any point in using a volatile long?

    - by Adamski
    I occasionally use a volatile instance variable in cases where I have two threads reading from / writing to it and don't want the overhead (or potential deadlock risk) of taking out a lock; for example a timer thread periodically updating an int ID that is exposed as a getter on some class: public class MyClass { private volatile int id; public MyClass() { ScheduledExecutorService execService = Executors.newScheduledThreadPool(1); execService.scheduleAtFixedRate(new Runnable() { public void run() { ++id; } }, 0L, 30L, TimeUnit.SECONDS); } public int getId() { return id; } } My question: Given that the JLS only guarantees that 32-bit reads will be atomic is there any point in ever using a volatile long? (i.e. 64-bit). Caveat: Please do not reply saying that using volatile over synchronized is a case of pre-optimisation; I am well aware of how / when to use synchronized but there are cases where volatile is preferable. For example, when defining a Spring bean for use in a single-threaded application I tend to favour volatile instance variables, as there is no guarantee that the Spring context will initialise each bean's properties in the main thread.

    Read the article

  • C# array of objects - conditional validation

    - by fishdump
    Sorry about the vague title! I have an class with a number of member variables (system, zone, site, ...) public sealed class Cello { public String Company; public String Zone; public String System; public String Site; public String Facility; public String Process; //... } I have an array of objects of this class. private Cello[] m_cellos = null; // ... I need to know whether the array contains objects with the same site but different systems, zones or companies since such a situation would be illegal. I have various other checks to make but they are all along similar lines. The Array class has a number of functions that look promising but I am not very up on defining 'key selector' functions and things like that. Any suggestions or pointers would be greatly appreciated. --- Alistair.

    Read the article

  • php script randomly hangs up

    - by sergdev
    I install php 5 (more precisely 5.3.1) as apache module. After this one of my application becomes randomly hang up on mysql_connect - sometimes works, sometimes no, sometimes reload of page helps. How can this be fixed? I use Windows Vista, Apache/2.2.14 (Win32) PHP/5.3.1 with php module, MySql 5.0.67-community-nt. After a minute I obtain the error message: Fatal error: Maximum execution time of 60 seconds exceeded in path\to\mysqlcon.php on line 9 I run MySql locally and heavy load could not be a reason: SHOW PROCESSLIST shows about 3 process SHOW VARIABLES LIKE 'MAX_CONNECTIONS' is 100. UPDATE: At first I thought that this is connected with mysql_connect. But now I can't say for certain. More difficult thing is when I insert the line to debug: $fh = fopen("E://_debugLog", 'a'); fwrite($fh, __FILE__ . " : " . __LINE__ . "\n"); fclose($fh); script start working near that location as a rule.

    Read the article

  • How does PHP interface with Apache?

    - by Sbm007
    Hi, I've almost finished writing a HTTP/1.0 compliant web server under Java (no commercial usage as such, this is just for fun) and basically I want to include PHP support. I realize that this is no easy task at all, but I think it'll be a nice accomplishment. So I want to know how PHP exactly interfaces with the Apache web server (or any other web server really), so I can learn from it and write my own PHP wrapper. It doesn't necessarily have to be mod_php, I don't mind writing a FastCGI wrapper - which to my knowledge is capable of running PHP as well. I would've thought that all that PHP needs is the output that goes to client (so it can interpret the PHP parts), the full HTTP request from client (so it can extract POST variables and such) and the client's host name. And then you simply take the parsed PHP code and write that to the output stream. There will probably be more things, but in essence that's how I would have thought it works. From what I've gathered so far, apache2handler provides an API which PHP makes use of to 'connect' to Apache. I guess it's an idea to look at the source code for apache2handler and php5apache2.dll or so, but before I do that I thought I'd ask SO first. If anyone has more information, experience, or some sort of specification that is relevant to this then please let me know. Thanks in advance!

    Read the article

  • Can't store UTF-8 in RDS despite setting up new Parameter Group using Rails on Heroku

    - by Lail
    I'm setting up a new instance of a Rails(2.3.5) app on Heroku using Amazon RDS as the database. I'd like to use UTF-8 for everything. Since RDS isn't UTF-8 by default, I set up a new Parameter Group and switched the database to use that one, basically per this. Seems to have worked: SHOW VARIABLES LIKE '%character%'; character_set_client utf8 character_set_connection utf8 character_set_database utf8 character_set_filesystem binary character_set_results utf8 character_set_server utf8 character_set_system utf8 character_sets_dir /rdsdbbin/mysql-5.1.50.R3/share/mysql/charsets/ Furthermore, I've successfully setup Heroku to use the RDS database. After rake db:migrate, everything looks good: CREATE TABLE `comments` ( `id` int(11) NOT NULL AUTO_INCREMENT, `commentable_id` int(11) DEFAULT NULL, `parent_id` int(11) DEFAULT NULL, `content` text COLLATE utf8_unicode_ci, `child_count` int(11) DEFAULT '0', `created_at` datetime DEFAULT NULL, `updated_at` datetime DEFAULT NULL, PRIMARY KEY (`id`), KEY `commentable_id` (`commentable_id`), KEY `index_comments_on_community_id` (`community_id`), KEY `parent_id` (`parent_id`) ) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci; In the markup, I've included: <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> Also, I've set: production: encoding: utf8 collation: utf8_general_ci ...in the database.yml, though I'm not very confident that anything is being done to honor any of those settings in this case, as Heroku seems to be doing its own config when connecting to RDS. Now, I enter a comment through the form in the app: "Úbe® ƒåiL", but in the database I've got "Úbe® Æ’Ã¥iL" It looks fine when Rails loads it back out of the database and it is rendered to the page, so whatever it is doing one way, it's undoing the other way. If I look at the RDS database in Sequel Pro, it looks fine if I set the encoding to "UTF-8 Unicode via Latin 1". So it seems Latin-1 is sneaking in there somewhere. Somebody must have done this before, right? What am I missing?

    Read the article

  • Gradual memory leak and slowdown in loop

    - by Benji XVI
    I have a simple foundation tool that exports every frame of a movie as a .tiff file. Here is the relevant code: NSString* movieLoc = [NSString stringWithCString:argv[1]]; QTMovie *sourceMovie = [QTMovie movieWithFile:movieLoc error:nil]; int i=0; while (QTTimeCompare([sourceMovie currentTime], [sourceMovie duration]) != NSOrderedSame) { // save image of movie to disk NSAutoreleasePool *arp = [[NSAutoreleasePool alloc] init]; NSString *filePath = [NSString stringWithFormat:@"/somelocation_%d.tiff", i++]; NSData *currentImageData = [[sourceMovie currentFrameImage] TIFFRepresentation]; [currentImageData writeToFile:filePath atomically:NO]; NSLog(@"%@", filePath); [sourceMovie stepForward]; [arp release]; } [pool drain]; return 0; As you can see, in order to prevent very large memory buildups with the various transparently-autoreleased variables in the loop, we create, and flush, an autoreleasepool with every run through the loop. However, over the course of stepping through a movie, the amount of memory used by the program still gradually increases, and the speed at which frames are processed drops precipitously. (From ~0.5 seconds per frame at the start, to ~2 seconds per frame by the 250th frame.) The only thing I can think can be causing the gradual memory leak is a buildup of the NSAutoreleasePool objects themselves. Am I right in thinking they will only be deallocated when the outer pool is released? If so, is there a better memory management solution here? Creating a pool every run through the loop seems a little hacky. And if not, what is causing the slow memory leak? (It is not NSStrings, and much too slow to be NSImages or NSDatas.) And what could be causing the slowdown?

    Read the article

  • What about parallelism across network using multiple PCs?

    - by MainMa
    Parallel computing is used more and more, and new framework features and shortcuts make it easier to use (for example Parallel extensions which are directly available in .NET 4). Now what about the parallelism across network? I mean, an abstraction of everything related to communications, creation of processes on remote machines, etc. Something like, in C#: NetworkParallel.ForEach(myEnumerable, () => { // Computing and/or access to web ressource or local network database here }); I understand that it is very different from the multi-core parallelism. The two most obvious differences would probably be: The fact that such parallel task will be limited to computing, without being able for example to use files stored locally (but why not a database?), or even to use local variables, because it would be rather two distinct applications than two threads of the same application, The very specific implementation, requiring not just a separate thread (which is quite easy), but spanning a process on different machines, then communicating with them over local network. Despite those differences, such parallelism is quite possible, even without speaking about distributed architecture. Do you think it will be implemented in a few years? Do you agree that it enables developers to easily develop extremely powerfull stuff with much less pain? Example: Think about a business application which extracts data from the database, transforms it, and displays statistics. Let's say this application takes ten seconds to load data, twenty seconds to transform data and ten seconds to build charts on a single machine in a company, using all the CPU, whereas ten other machines are used at 5% of CPU most of the time. In a such case, every action may be done in parallel, resulting in probably six to ten seconds for overall process instead of forty.

    Read the article

  • The linking is not done (gcc compilation)

    - by Moons
    Hello everyone! So i have this issue : i am declaring some extern global variables in my C program. If I don't use the -c option for gcc, i get undefined references errors. But with that -c option, the linking is not done, which means that i don't have an executable generated. So how do I solve this? Here is my makefile. As I am not good with writing makefiles, I took one from another project then I changed a few things. So maybe I'm missing something here. # Makefile calculPi INCL = -I$(INCL_DIR) DEFS = -D_DEBUG_ CXX_FLAGS =-g -c -lpthread -lm CXX = gcc $(CXX_FLAGS) $(INCL) $(DEFS) LINK_CXX = gcc OBJ = approx.o producteur.o sequentialApproximation.o main.o LINKOBJ = approx.o producteur.o sequentialApproximation.o main.o BIN = calculPi.exe RM = rm -fv all: calculPi.exe clean: ${RM} *\~ \#*\# $(OBJ) clean_all: clean ${RM} $(BIN) cleanall: clean ${RM} $(BIN) $(BIN): $(OBJ) $(CXX) $(LINKOBJ) -o "calculPi.exe" main.o: main.c $(CXX) main.c -o main.o $(CXX_FLAGS) approx.o: approx.c approx.h $(CXX) -c approx.c -o approx.o $(CXX_FLAGS); producteur.o: producteur.c producteur.h $(CXX) -c producteur.c -o producteur.o $(CXX_FLAGS); sequentialApproximation.o : sequentialApproximation.c sequentialApproximation.h $(CXX) -c sequentialApproximation.c -o sequentialApproximation.o $(CXX_FLAGS);

    Read the article

  • Client Side Only Cookies

    - by Mike Jones
    I need something like a cookie, but I specifically don't want it going back to the server. I call it a "client side session cookie" but any reasonable mechanism would be great. Basically, I want to store some data encrypted on the server, and have the user type a password into the browser. The browser decrypts the data with the password (or creates and encrypts the data with the password) and the server stores only encrypted data. To keep the data secure on the server, the server should not store and should never receive the password. Ideally there should be a cookie session expiration to clean up. Of course I need it be available on multiple pages as the user walks through the web site. The best I can come up with is some sort of iframe mechanism to store the data in javascript variables, but that is ugly. Does anyone have any ideas how to implement something like this? FWIW, the platform is ASP.NET, but I don't suppose that matters. It needs to support a broad range of browsers, including mobile. In response to one answer below, let me clarify. My question is not how to achieve the crypto, that isn't a problem. The question is where to store the password so that it is persistent from page to page, but not beyond a session, and in such a way that the server doesn't see it.

    Read the article

  • Segmentation fault on returning from main (very short and simple code, no arrays or pointers)

    - by Gábor Kovács
    I've been wondering why the following trivial code produces a segmentation fault when returning from main(): //Produces "Error while dumping state (probably corrupted stack); Segmentation fault" #include <iostream> #include <fstream> #include <vector> using namespace std; class Test { vector<int> numbers; }; int main() { Test a; ifstream infile; cout << "Last statement..." << endl; // this gets executed return 0; } Interestingly, 1) if only one of the two variables is declared, I don't get the error, 2) if I declare a vector variable instead of an object with a vector member, everything's fine, 3) if I declare an ofstream instead of an ifstream, again, everything works fine. Something appears to be wrong with this specific combination... Could this be a compiler bug? I use gcc version 3.4.4 with cygwin. Thanks for the tips in advance. Gábor

    Read the article

  • Thread mutex behaviour

    - by Alberteddu
    Hi there, I'm learning C. I'm writing an application with multiple threads; I know that when a variable is shared between two or more threads, it is better to lock/unlock using a mutex to avoid deadlock and inconsistency of variables. This is very clear when I want to change or view one variable. int i = 0; /** Global */ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; /** Thread 1. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); /** Thread 2. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); This is correct, I think. The variable i, at the end of the executions, contains the integer 2. Anyway, there are some situations in which I don't know exactly where to put the two function calls. For example, suppose you have a function obtain(), which returns a global variable. I need to call that function from within the two threads. I have also two other threads that call the function set(), defined with a few arguments; this function will set the same global variable. The two functions are necessary when you need to do something before getting/setting the var. /** (0) */ /** Thread 1, or 2, or 3... */ if(obtain() == something) { if(obtain() == somethingElse) { // Do this, sometimes obtain() and sometimes set(random number) (1) } else { // Do that, just obtain(). (2) } } else { // Do this and do that (3) // If # of thread * 3 > 10, then set(3*10) For example. (4) } /** (5) */ Where I have to lock, and where I have to unlock? The situation can be, I think, even more complex. I will appreciate an exhaustive answer. Thank you in advance. —Alberto

    Read the article

  • Java: Comparing a class with another within that class using a my own .equals

    - by user1670252
    I am making a method .equals replacing the equals method used. It accepts a object. I want it to check if that object equals the class that runs the .equals class. I know I want to compare all the private methods I have to that object. Is there a way to do this without making another private class to get the private variables from the object? How do I do this to compare equality not identity? I am stuck on this. Do i have to use == to compare? Also looking online i see others use recursion. If this is the way i have to do it can you show and explain it to me? so an example i have public boolean equals(Object o) { this is in a class we will call bobtheBuilder (first thing to pop in my head) I want to check if the object o is equal to the class he has private object array and a private int. I assume I want to check if the array and int of this class equal the array and int of the object.

    Read the article

  • Using array instead of lots of db queries in PHP

    - by Tural Teyyuboglu
    My function looks like that. It works but does lots of work (recursively calls itself and does lots of db queries.). There must be another way to do same thing but with array (with one query). I can't figure out how to modify this function to get it work with array. Please help. function genMenu($parent, $level, $menu, $utype) { global $db; $stmt=$db->prepare("select id, name FROM navigation WHERE parent = ? AND menu=? AND user_type=?") or die($db->error); $stmt->bind_param("iii", $parent, $menu, $utype) or die($stmt->error); $stmt->execute() or die($stmt->error); $stmt->store_result(); /* bind variables to prepared statement */ $stmt->bind_result($id, $name) or die($stmt->error); if ($level > 0 && $stmt->num_rows > 0) { echo "\n<ul>\n"; } while ($stmt->fetch()) { echo "<li>"; echo '<a href="?page=' . $id . '">' . $name . '</a>'; //display this level's children genMenu($id, $level+1, $menu, $utype); echo "</li>\n\n"; } if ($level > 0 && $stmt->num_rows > 0) { echo "</ul>\n"; } $stmt->close(); }

    Read the article

  • Asp.Net 2 integrated sites How to Logout second site programatically.

    - by NBrowne
    Hi , I am working with an asp.net 2.0 site (call it site 1) which has an iframe in it which loads up another site (site2) which is also an asp.net site which is developed by our team. When you log onto site 1 then behind the scenes site 2 is also logged in so that when you click the iframe tab then this displays site 2 with the user logged in (to prevent the user from having to log in twice). The problem i have is that when a user logs out of site 1 then we call some cleanup methods to perform FormsAuthentication.SignOut and clean session variables etc but at the moment no cleanup is called when the user on site 2. So the issue is that if the user opens up Site 2 from within a browser then website 2 opens with the user still logged in which is undesired. Can anyone give me some guidance as to the best approach for this?? One possible approach i though of was just that on click of logout button i could do a call to a custom page on Site 2 which would do the logout. Code below HttpWebRequest request; request = ((HttpWebRequest)(WebRequest.Create("www.mywebsite.com/Site2Logout.aspx"))); request.Method = "POST"; HttpCookie cookie = HttpContext.Current.Request.Cookies[FormsAuthentication.FormsCookieName]; Cookie authenticationCookie = new Cookie( FormsAuthentication.FormsCookieName, cookie.Value, cookie.Path, HttpContext.Current.Request.Url.Authority); request .CookieContainer = new CookieContainer(); request .CookieContainer.Add(authenticationCookie); response.GetResponse(); Problem i am having with this code is that when i run it and debug on Site 2 and check to see if the user is Authenticated they are not which i dont understand because if i open browser and browse to Site 2 i am Still authenticated. Any ideas , different direction to take etc ??? Please let me know if you need any more info or if i something i have said dosent make sense. Thanks

    Read the article

  • The proper way to script periodically pulling a page from an https site

    - by DarthShader
    I want to create a command-line script for Cygwin/Bash that logs into a site, navigates to a specific page and compares it with the results of the last run. So far, I have it working with Lynx like so: ----snpipped, just setting variables---- echo "# Command logfile created by Lynx 2.8.5rel.5 (29 Oct 2005) ----snipped the recorded keystrokes------- key Right Arrow key p key Right Arrow key ^U" >> $tmp1 #p, right arrow initiate the page saving #"type" the filename inside the "where to save" dialog for i in $(seq 0 $((${#tmp2} - 1))) do echo "key ${tmp2:$i:1}" >> $tmp1 done #hit enter and quit echo "key ^J key y key q key y " >> $tmp1 lynx -accept_all_cookies -cmd_script=$tmp1 https://thewebpage.com/login diff $tmp2 $oldComp mv $tmp2 $oldComp It definitely does not feel "right": the cmd_script consists of relative user actions instead of specifying the exact link names and actions. So, if anything on the site ever changes, switches places, or a new link is added - I will have to re-create the actions. Also, I can't check for any errors so I can't abort the script if something goes wrong (login failed, etc) Another alternative I have been looking at is Mechanize with Ruby (as a note - I have 0 experience with Ruby). What would be the best way to improve or rewrite this?

    Read the article

< Previous Page | 320 321 322 323 324 325 326 327 328 329 330 331  | Next Page >