Search Results

Search found 29841 results on 1194 pages for 'random number generator'.

Page 453/1194 | < Previous Page | 449 450 451 452 453 454 455 456 457 458 459 460  | Next Page >

  • Are there any downsides in using C++ for network daemons?

    - by badcat
    Hey guys! I've been writing a number of network daemons in different languages over the past years, and now I'm about to start a new project which requires a new custom implementation of a properitary network protocol. The said protocol is pretty simple - some basic JSON formatted messages which are transmitted in some basic frame wrapping to have clients know that a message arrived completely and is ready to be parsed. The daemon will need to handle a number of connections (about 200 at the same time) and do some management of them and pass messages along, like in a chat room. In the past I've been using mostly C++ to write my daemons. Often with the Qt4 framework (the network parts, not the GUI parts!), because that's what I also used for the rest of the projects and it was simple to do and very portable. This usually worked just fine, and I didn't have much trouble. Being a Linux administrator for a good while now, I noticed that most of the network daemons in the wild are written in plain C (of course some are written in other languages, too, but I get the feeling that 80% of the daemons are written in plain C). Now I wonder why that is. Is this due to a pure historic UNIX background (like KISS) or for plain portability or reduction of bloat? What are the reasons to not use C++ or any "higher level" languages for things like daemons? Thanks in advance! Update 1: For me using C++ usually is more convenient because of the fact that I have objects which have getter and setter methods and such. Plain C's "context" objects can be a real pain at some point - especially when you are used to object oriented programming. Yes, I'm aware that C++ is a superset of C, and that C code is basically C++. But that's not the point. ;)

    Read the article

  • javascript hide/show tabs using JQuery

    - by JohnMerlino
    Hey all, I have a quick question of how I can use jquery tabs (you click on link button to display/hide certain divs). The div id matches the href of the link: HTML links: <table class='layout tabs'> <tr> <td><a href="#site">Site</a></td> <td><a href="#siteno">Number</a></td> </tr> <tr> <td><a href="#student">Student</a></td> <td><a href="#school">School</a></td> </tr> </table> </div> div that needs to display/hide: <div id="site"> <table class='explore'> <thead class='ui-widget-header'> <tr> <th class=' sortable'> Site </th> <th class=' sortable'> Number </th> </tr> </thead> </table> </div> Thanks for any response.

    Read the article

  • Why does OVFTool hang randomly?

    - by Billy ONeal
    Hello everyone :) Some great helpers here have shown me the VMWare OVF tool for template deployment. My problem is that the tool itself stops at the "Disk Transfer Completed" step half the time I use it. This seems to be random, and when it happens I have to terminate OVFTool and start the transfer over again. The second attempt usually succeeds. Is there something I have broken on the server that might affect this? I'm using the free edition of ESXi 4.0. Billy3

    Read the article

  • MSBuild: automate collecting of db migration scripts?

    - by P Dub
    Summary of environment. Asp.net web application (source stored in svn) sqlserver database. (Database schema (tables/sprocs) stored in svn) db version is synced with web application assembly version. (stored in table 'CurrentVersion') CI hudson server that checks out web app from repo and runs custom msbuild file to publish/package app. My msbuild script updates the assembly version of the web app (Major.Minor.Revision.Build) on each build. The 'Revision' is set to the currently checked out svn revision and the 'Build' to the hudson build number (incremented on each automated build). This way i can match the app to a specific trunk revision also get other build stats from the hudson build number. I'd like to automate the collecting of migration scripts (updated sprocs etc) to add to the zip package. I guess by comparing the svn revision of the db that has yet to be deployed to, to the revision being deployed, i can find what db files have changed in the trunk since the last deployment to that database/environment. This could easily be achieved by manually calling the svn diff -r REVNO:REVNO command to list changed .sql files. These files could then manually have to be added to the package. It would be great if this could be automated. Firstly i'd imagine I'll have to write a custom task to check the version of the db that has yet to be deployed to. After that I'm quite unsure. Does anyone have any suggestion on how this would be achieved through an msbuild task either existing or custom? Finally I'll have to autogen a script to add to the package that updates the database version table so as to be in sync with the application.

    Read the article

  • Use PermGen space or roll-my-own intern method?

    - by Adamski
    I am writing a Codec to process messages sent over TCP using a bespoke wire protocol. During the decode process I create a number of Strings, BigDecimals and dates. The client-server access patterns mean that it is common for the client to issue a request and then decode thousands of response messages, which results in a large number of duplicate Strings, BigDecimals, etc. Therefore I have created an InternPool<T> class allowing me to intern each class of object. Internally, the pool uses a WeakHashMap<T, WeakReferemce<T>>. For example: InternPool<BigDecimal> pool = new InternPool<BigDecimal>(); ... // Read BigDecimal from in buffer and then intern. BigDecimal quantity = pool.intern(readBigDecimal(in)); My question: I am using InternPool for BigDecimal but should I consider also using it for String instead of String's intern() method, which I believe uses PermGen space? What is the advantage of using PermGen space?

    Read the article

  • php and mysql site design question

    - by Jacksta
    I am trying to build a website with mysql and php. This is the first site I have attempted so I want to write a little plan and get some feedback. The site allows users to add some text in a text field as a “comment”. Once the comment has been entered into the site it is added to the database where it can be voted for by other users. When a new comment has been added to the database it needs to create a new page, e.g. www.xxxxx.com/commentname or www.xxxxxx.com/?id=99981. There will be a list of "Comments" in the database along with the number of votes for each comment. The home page will have two functions. 1) Allow users to add a "comment" 2) Display two tables, each with 20 rows containing most "popular comments" and "recent comments" Each comment will generate its one page where the comment will be displayed. Here users can read the comment and Vote for the comment if they wish. Please help me out by explaining how to do the following. -Generate a new page whenever a comment is added to the database -Add a vote to the vote count in the comment database. -Display the top 20 most popular comments as per number of votes.

    Read the article

  • How do you work around memcached's key/value limitations?

    - by mjy
    Memcached has length limitations for keys (250?) and values (roughtly 1MB), as well as some (to my knowledge) not very well defined character restrictions for keys. What is the best way to work around those in your opinion? I use the Perl API Cache::Memcached. What I do currently is store a special string for the main key's value if the original value was too big ("parts:<number") and in that case, I store <number parts with keys named 1+<main key, 2+<main key etc.. This seems "OK" (but messy) for some cases, not so good for others and it has the intrinsic problem that some of the parts might be missing at any time (so space is wasted for keeping the others and time is wasted reading them). As for the key limitations, one could probably implement hashing and store the full key (to work around collisions) in the value, but I haven't needed to do this yet. Has anyone come up with a more elegant way, or even a Perl API that handles arbitrary data sizes (and key values) transparently? Has anyone hacked the memcached server to support arbitrary keys/values?

    Read the article

  • Jquery Sorting by Letter

    - by Batfan
    I am using jquery to sort through a group of paragraph tags (kudos to Aaron Harun). It pulls the value "letter" (a letter) from the url string and displays only paragraphs that start with that letter. It hides all others and also consolidates the list so that there are no duplicates showing. See the code: var letter = '<?php echo(strlen($_GET['letter']) == 1) ? $_GET['letter'] : ''; ?>' function finish(){ var found_first = []; jQuery('p').each(function(){ if(jQuery(this).text().substr(0,1).toUpperCase() == letter){ if(found_first[jQuery(this).text()] != true){ jQuery(this).addClass('current-series'); found_first[jQuery(this).text()] = true; }else{ jQuery(this).hide(); } } else{ jQuery(this).hide();} }) } Been working with this all day and I have 2 Questions on this: Is there a way to get it to ignore the word 'The', if it's first? For example, if a paragraph starts with 'The Amazing', I would like it to show up on the 'A' page, not the 'T' page, like it currently is. Is there a way to have a single page for (all) numbers? For example, the url to the page would be something similar to domain.com/index.php?letter=0 and this would show only the paragraph tags that start with a number, any number. I can currently do this with single numbers but, I would like 1 page for all numbers.

    Read the article

  • How can I find the jdbc connection timeout of a hibernate session

    - by StevenWilkins
    I currently have a long running thread which uses a hibernate session to perform many updates. We currently have our c3p0 connection timeout set to 20 minutes and it's timing out sometimes because of the number of updates we're performing. The solution I have is to periodically return the connection to the pool via closing the session (we have hibernate configured this way) and get a new one. Upping the timeout is not desirable because the same pool is used for the entire application. The problem is I don't know when to return the connection to the pool because I don't know what the timeout of the connection is. I know what the current setting is in our property file, but that can be changed without my knowledge at any time so it's fragile. Having a counter and returning the connection based on the number of updates I've performed is not ideal but could be my option of last resort. I have a hibernate session, how can I retrieve the connection timeout of the jdbc connection which backs the session? Using the SessionFactory and SessionFactoryImpl classes are perfectly acceptable.

    Read the article

  • How to open a program on particular desktop?

    - by Vi.
    When I start GUI program, it's window appears appears on currently active desktop (essentially, on random desktop). How to make it to appear on the specified desktop? For example, at startup I want certain programs to be started and distributed to desktops. I've already set up config file of openbox to force some programs to always start on specific desktop. Ideally it should be like: start_on_desktop 1 gnome-terminal --tab -e program1 --tab -e program2 start_on_desktop 2 gnome-terminal --tab -e program3 --tab -e program4 start_on_desktop 3 firefox It should be able to start the same program on other desktop. Also dislike when I start program while being on desktop X then switch to desktop Y and SUDDENLY a program which should be on X appears on Y. When I start lots of programs on and switch often between desktops they end up being in chaos and I need to collect them together and redistribute sanely. Also I want the first initial gnome-terminal to be on desktop 3, but I also want subsequent gnome-terminals to be on the desktop where I pressed the keystroke (also configured in openbox) that launches gnome-terminal.

    Read the article

  • Screenflick Audio option in MacBook Pro

    - by John
    When after I shut down my MacBook Pro by holding the power button for a few sec, (which I found is bad for the computer, so I will not do anymore) I found that my speaker doesn't play until I plug in and out earphone into the machine. When my speaker is not working like this, and when I am on a random webcam chatting site like chatroulette.com, they can hear the music playing on my iTunes when I choose Screenflick Audio option in the Mic setting. But when the Speaker is working back again, they don't hear the music playing even when I do Screenflick Audio mode. How can I make it work? Also, how do you make the chatting partner hear my music playing on my computer while I talk to them (not via my speaker, since it's bad quality).

    Read the article

  • Rendering artifact when using Eclipse (FlashBuilder)

    - by Demian Brecht
    Once in a while when using FlashBuilder, I'll get a rendering artifact that doesn't go away until I do a full reboot. This artifact seems to be caused by a popup triggered by code documentation popups (hovering over keywords) that linger after the popup has been dismissed: This behavior is seemingly random and incredibly annoying. It only happens when using Eclipse (although I don't run many Java-based programs) and run an NVidia Quadro 2000M (with the latest drivers - figured I'd try that before posting). Has anyone else encountered this issue? Any known solutions?

    Read the article

  • Total Average Week using a Parameter

    - by Jose
    I have a crystal report that shows sales volumes called week to date volume. It shows current week, previous week, and average week. The report prompts for a date parameter and I extract the week number to get current week and previous week volumes. Did it this way because Mngmt wants to be able to run report whenever. My problem is for Average Week I cant figure out how to get the number of weeks to divide by for my average. Report originates from June 1st, 2010. Right now I have: DATEPART("ww", {?date}) - DATEPART("ww", DATE(2010, 6, 1)) This returns 2 right now which is perfect, so i divide my total by 2. This code will work until the end of the year then I'm hooped. Any idea how I can make this a little more dynamic. I was thinking a counter somehow, just can't get the logic down because the date parameter will keep changing, meaning I cant increase my counter by 1 after each week??? Cheers.

    Read the article

  • script to test mail server

    - by WebDude
    Ever since a windows update that took down my IIS6 mail server a few weeks back, I've been really paranoid about my mail server working. So every time I run a windows update I fire up command prompt and send myself a quick test mail. Like so: > telnet localhost 25 > helo domain.com > mail from: [email protected] > rcpt to: [email protected] > data some random body to mail myself . This is a realy great way to test my mail server, but it's a pain in the neck to do quickly. Is there anyway i can run this in a batch script or something as a quick test? I've tried a bat file but this just waits after i call telnet I've also explored if telnet accepts any input files and it does not seem to. What's the best way to do this?

    Read the article

  • Working with fields which can mutate or be new instances altogether

    - by dotnetdev
    Structs are usually used for immutable data, eg a phone number, which does not mutate, but instead you get a new one (eg the number 000 becoming 0001 would mean two seperate numbers). However, pieces of information like Name, a string, can either mutate (company abc changing its name to abcdef, or being given a new name like def). For fields like this, I assume they should reside in the mutable class and not an immutable structure? My way of structuring code is to have an immutable concept, like Address (any change is a new address completely), in a struct and then reference it from a class like Customer, since Customer always has an address. So I would put CompanyName, or Employer, in the class as it is mutable. But a name can either mutate and so be the same 1 instance, or a new name setup and while the company still owning the first name too. Would the correct pattern for assigning a new instance (eg a new company name but the old name still owned by the company) be?: string name = ""; string newName = new string(); newName = "new"; name = newName; And a mutation just the standard assignment pattern? Thanks

    Read the article

  • 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

    Read the article

  • Drawing and filling different polygons at the same time in MATLAB

    - by Hossein
    Hi,I have the code below. It load a CSV file into memory. This file contains the coordinates for different polygons.Each row of this file has X,Y coordinates and a string which tells that to which polygon this datapoint belongs. for example a polygone named "Poly1" with 100 data points has 100 rows in this file like : Poly1,X1,Y1 Poly1,X2,Y2 ... Poly1,X100,Y100 Poly2,X1,Y1 ..... The index.csv file has the number of datapoint(number of rows) for each polygon in file Polygons.csv. These details are not important. The thing is: I can successfully extract the datapoints for each polygon using the code below. However, When I plot the lines of different polygons are connected to each other and the plot looks crappy. I need the polygons to be separated(they are connected and overlapping the some areas though). I thought by using "fill" I can actually see them better. But "fill" just filles every polygon that it can find and that is not desirable. I only want to fill inside the polygons. Can someone help me? I can also send you my datapoint if necessary, they are less than 200Kb. Thanks [coordinates,routeNames,polygonData] = xlsread('Polygons.csv'); index = dlmread('Index.csv'); firstPointer = 0 lastPointer = index(1) for Counter=2:size(index) firstPointer = firstPointer + index(Counter) + 1 hold on plot(coordinates(firstPointer:lastPointer,2),coordinates(firstPointer:lastPointer,1),'r-') lastPointer = lastPointer + index(Counter) end

    Read the article

  • Am I doing it right?

    - by LuckySlevin
    I have situation. I have to create a Sports Club system in JAVA. There should be a class your for keeping track of club name, president name and braches the club has. For each sports branch also there should be a class for keeping track of a list of players. Also each player should have a name, number, position and salary. So, I come up with this. Three seperate classes: public class Team { String clubName; String preName; Branch []branches; } public class Branch { Player[] players; } public class Player { String name; String pos; int salary; int number; } The problems are creating Branch[] in another class and same for the Player[]. Is there any simplier thing to do this? For example, I want to add info for only the club name, president name and branches of the club, in this situation, won't i have to enter players,names,salaries etc. since they are nested in each other. I hope i could be clear. For further questions you can ask.

    Read the article

  • ssh into my mac from my ipod

    - by mechko
    Ok so this is what I got, but it don't look right... The set up is as follows: My Mac is on a wireless network, presumably behind a firewall over which I have no admin privileges. Further, said wireless network changes my internal IP randomly at random times, so I do not know what my ip is. Note that localhost is a variable ip I forward some port or the other to my dns: ssh -R 19999:localhost:22 sourceuser@remotehost connect to my remotehost from my machine: ssh sourceuser@remotehost and then connect to the port I forwarded: ssh localhost -p 19999 [solved] Second question, there are a bunch of ssh clients for the iphone. Which one should I use? EDIT: Since jailbreak is not illegal, simply frowned upon by the Corporation, I've decided to go with that. I have a nice shell with openssh and the works. Best of all, it's free and it does exactly what you expect.

    Read the article

  • ios UITableView reloadData don't increase content height

    - by Zoltan Varadi
    I'm facing a strange error in my iOS app and haven't been able to figure out the reason why. In my UITableView i can add new cells, so i refresh the array that is the datasource and call reloadData. Everything works without error. The numberOfRowsInSection is called again, and it's value is one more than it's previous value was. The new cell even gets inserted at the bottom of the tableview, but i cant scroll down to it. I only know that it's there because the tableview bounces and i can see it. I'm guessing the tableview's content height is not getting increased for some reason, but i have no idea why. I'm using iOS 6 btw. Any help is very much appreciated! Thanks, Zoli EDIT, answers for Srikanth's questions: How is data getting added. There's an NSArray containing objects of a specific type. The array.count is the number of the number of cells. This NSArray gets its values from a database query. When you say, you are refreshing the array, what do you mean. By refreshing the array i mean i execute a new query in the database and put the results of this query into an NSArray. this will be the tableview's datasource array. Like this: dataSourceArray = [dbManager executeQuery]; [tableView reloadData]; Are you adding the data within the same view controller Yes. Can you show some code as to what you are doing See above. Is the table view at the root of the view controllers view or is it within another view The tableview is the main view's first child. Can you try adding data to the array at the beginning, so that you can view the cell being added at the top. I don't understand what you mean.

    Read the article

  • Problem with checkboxes, sql select statements & php

    - by smokey20
    I am trying to display some rows from a database table based on choices submitted by the user. Here is my form code <form action="choice.php" method="POST" > <input type="checkbox" name="variable[]" value="Apple">Apple <input type="checkbox" name="variable[]" value="Banana">Banana <input type="checkbox" name="variable[]" value="Orange">Orange <input type="checkbox" name="variable[]" value="Melon">Melon <input type="checkbox" name="variable[]" value="Blackberry">Blackberry From what I understand I am placing the values of these into an array called variable. Two of my columns are called receipe name and ingredients(each field under ingredients can store a number of fruits). What I would like to do is, if a number of checkboxes are selected then the receipe name/s is displayed. Here is my php code. <?php // Make a MySQL Connection mysql_connect("localhost", "*****", "*****") or die(mysql_error()); mysql_select_db("****") or die(mysql_error()); $variable=$_POST['variable']; foreach ($variable as $variablename) { echo "$variablename is checked"; } $query = "SELECT receipename FROM fruit WHERE $variable like ingredients"; $row = mysql_fetch_assoc($result); foreach ($_POST['variabble'] as $ingredients) echo $row[$ingredients] . '<br/>'; ?> I am very new to php and just wish to display the data, I do not need to perform any actions on it. I have tried many select statements but I cannot get any results to display. My db connection is fine and it does print out what variables are checked. Many thanks in advance.

    Read the article

  • Formatting the output of a custom tool so I can double click an error in Visual Studio and the file opens

    - by Ben Scott
    I've written a command line tool that preprocesses a number of files then compiles them using CodeDom. The tool writes a copyright notice and some progress text to the standard output, then writes any errors from the compilation step using the following format: foreach (var err in results.Errors) { // err is CompilerError var filename = "Path\To\input_file.xprt"; Console.WriteLine(string.Format( "{0} ({1},{2}): {3}{4} ({5})", filename, err.Line, err.Column, err.IsWarning ? "" : "ERROR: ", err.ErrorText, err.ErrorNumber)); } It then writes the number of errors, like "14 errors". This is an example of how the error appears in the console: Path\To\input_file.xrpt (73,28): ERROR: An object reference is required for the non-static field, method, or property 'Some.Object.get' (CS0120) When I run this as a custom tool in VS2008 (by calling it in the post-build event command line of one of my project's assemblies), the errors appear nicely formatted in the Error List, with the correct text in each column. When I roll over the filename the fully qualified path pops up. The line and column are different to the source file because of the preprocessing which is fine. The only thing that stands out is that the Project given in the list is the one that has the post-build event. The problem is that when I double click an error, nothing happens. I would have expected the file to open in the editor. I'm vaugely aware of the Microsoft.VisualStudio.Shell.Interop namespace but I think it should be possible just by writing to the standard output.

    Read the article

  • jquery calculation sum two different type of item

    - by st4n
    I'm writing a script like the example shown in the demo where All of the "Total" values (Including the "Grand Total") are Automatically Calculated using the calc () method. at this link: But I have some fields in which to apply the equation qty * price, and others where I want to do other operations .. you can tell me how? thank you very much i try with this, but it is a very stupid code .. and the grandTotal .. not sum the two different fields: function recalc() { $("[id^=total_item]").calc("qty * price", { qty: $("input[name^=qty_item_]"), price: $("[id^=price_item_]") }, function (s){ // return the number as a dollar amount return "$" + s.toFixed(2); }, function ($this){ // sum the total of the $("[id^=total_item]") selector var sum = $this.sum(); $("#grandTotal").text( // round the results to 2 digits "$" + sum.toFixed(2) ); }); $("[id^=total_otheritem]").calc("qty1 / price1", { qty1: $("input[name^=qty_other_]"), price1: $("[id^=price_other_]") }, function (s){ // return the number as a dollar amount return "$" + s.toFixed(2); }, function ($this){ var sum = $this.sum(); $("#grandTotal").text( // round the results to 2 digits "$" + sum.toFixed(2) ); }); }

    Read the article

  • I need to make a multithreading program (python)

    - by Andreawu98
    import multiprocessing import time from itertools import product out_file = open("test.txt", 'w') P = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p','q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',] N = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] M = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'] c = int(input("Insert the number of digits you want: ")) n = int(input("If you need number press 1: ")) m = int(input("If you need upper letters press 1: ")) i = [] if n == 1: P = P + N if m == 1: P = P + M then = time.time() def worker(): for i in product(P, repeat=c): #check every possibilities k = '' for z in range(0, c): # k = k + str(i[z]) # print each possibility in a txt without parentesis or comma out_file.write( k + '\n') # out_file.close() now = time.time() diff = str(now - then) # To see how long does it take print(diff) worker() time.sleep(10) # just to check console The code check every single possibility and print it out in a test.txt file. It works but I really can't understand how can I speed it up. I saw it use 1 core out of my quad core CPU so I thought Multi-threading might work even though I don't know how. Please help me. Sorry for my English, I am from Italy.

    Read the article

  • wireless dropping out

    - by Sam
    My wireless network connection is dropping out and its driving me nuts. It is weird because it happens at totally random intervals and other devices work while my computer has been dropped. Both my USB dongle and wifi card randomly disconnect from the router and I am unable to connect for a couple of minutes. It is especially irritating because two different adapters are failing at the same time, sounds like a software problem to me, but where? Both my laptop and iPod remain connected when the connection drops. What on earth is happening? I doubt its the router because the other devices would disconnect as well.

    Read the article

< Previous Page | 449 450 451 452 453 454 455 456 457 458 459 460  | Next Page >