Search Results

Search found 3363 results on 135 pages for 'postfix operator'.

Page 87/135 | < Previous Page | 83 84 85 86 87 88 89 90 91 92 93 94  | Next Page >

• Arguments for a coding standard?

  - by acidzombie24

  A few friends and i are planning to work on a project together and we want a COMPLETELY DIFFERENT coding standard. We do NOT want to use the coding standard the libraries/language uses. Its our project and we want to mess around. So i came here to ask what you guys think are good standards and arguments for it (or what not to do and arguments against it). The styles i remember most are Upper casing the entire word Camel and Pascal casing Using '_' to separate each word pre or postfixing letters or words (i hate m for member but i think IsCond() is a good func name. SomethingException as a postfix example) Using '_' at the start or end of words Brace placement. On a new or same line? I know of libs that use Pascal casing on all public and protected members. But would you ever get confused if something is a func, var or even property if the lang supports it? What about if you decide a public member to be private (or vice versa) wouldnt that great a lot of fix up work or inconsistencies? Is prefixing C to every class a good idea? I ask what do you think and why?

  Read the article

• yield – Just yet another sexy c# keyword?

  - by George Mamaladze

  yield (see NSDN c# reference) operator came I guess with .NET 2.0 and I my feeling is that it’s not as wide used as it could (or should) be.   I am not going to talk here about necessarity and advantages of using iterator pattern when accessing custom sequences (just google it).   Let’s look at it from the clean code point of view. Let's see if it really helps us to keep our code understandable, reusable and testable.   Let’s say we want to iterate a tree and do something with it’s nodes, for instance calculate a sum of their values. So the most elegant way would be to build a recursive method performing a classic depth traversal returning the sum.           private int CalculateTreeSum(Node top)         {             int sumOfChildNodes = 0;             foreach (Node childNode in top.ChildNodes)             {                 sumOfChildNodes += CalculateTreeSum(childNode);             }             return top.Value + sumOfChildNodes;         }     “Do One Thing” Nevertheless it violates one of the most important rules “Do One Thing”. Our  method CalculateTreeSum does two things at the same time. It travels inside the tree and performs some computation – in this case calculates sum. Doing two things in one method is definitely a bad thing because of several reasons: ·          Understandability: Readability / refactoring ·          Reuseability: when overriding - no chance to override computation without copying iteration code and vice versa. ·          Testability: you are not able to test computation without constructing the tree and you are not able to test correctness of tree iteration.   I want to spend some more words on this last issue. How do you test the method CalculateTreeSum when it contains two in one: computation & iteration? The only chance is to construct a test tree and assert the result of the method call, in our case the sum against our expectation. And if the test fails you do not know wether was the computation algorithm wrong or was that the iteration? At the end to top it all off I tell you: according to Murphy’s Law the iteration will have a bug as well as the calculation. Both bugs in a combination will cause the sum to be accidentally exactly the same you expect and the test will PASS. J   Ok let’s use yield! That’s why it is generally a very good idea not to mix but isolate “things”. Ok let’s use yield!           private int CalculateTreeSumClean(Node top)         {             IEnumerable<Node> treeNodes = GetTreeNodes(top);             return CalculateSum(treeNodes);         }             private int CalculateSum(IEnumerable<Node> nodes)         {             int sumOfNodes = 0;             foreach (Node node in nodes)             {                 sumOfNodes += node.Value;             }             return sumOfNodes;         }           private IEnumerable<Node> GetTreeNodes(Node top)         {             yield return top;             foreach (Node childNode in top.ChildNodes)             {                 foreach (Node currentNode in GetTreeNodes(childNode))                 {                     yield return currentNode;                 }             }         }   Two methods does not know anything about each other. One contains calculation logic another jut the iteration logic. You can relpace the tree iteration algorithm from depth traversal to breath trevaersal or use stack or visitor pattern instead of recursion. This will not influence your calculation logic. And vice versa you can relace the sum with product or do whatever you want with node values, the calculateion algorithm is not aware of beeng working on some tree or graph.  How about not using yield? Now let’s ask the question – what if we do not have yield operator? The brief look at the generated code gives us an answer. The compiler generates a 150 lines long class to implement the iteration logic.       [CompilerGenerated]     private sealed class <GetTreeNodes>d__0 : IEnumerable<Node>, IEnumerable, IEnumerator<Node>, IEnumerator, IDisposable     {         ...        150 Lines of generated code        ...     }   Often we compromise code readability, cleanness, testability, etc. – to reduce number of classes, code lines, keystrokes and mouse clicks. This is the human nature - we are lazy. Knowing and using such a sexy construct like yield, allows us to be lazy, write very few lines of code and at the same time stay clean and do one thing in a method. That's why I generally welcome using staff like that.   Note: The above used recursive depth traversal algorithm is possibly the compact one but not the best one from the performance and memory utilization point of view. It was taken to emphasize on other primary aspects of this post.

  Read the article

• How to install and Configure MTA on Linux [closed]

  - by Umair Mustafa

  I need to know which MTA's is better and simple to handle and configure in linux. As I need to run a script that will send me the output of that command whenever it will run using cron. Ok the case is this. Every day I have to manually check the Disk space of server which are more than 30 which is headache and have to document that. So I will simply add the follwing command DF- H and the output of this command should be send on my email. So now IF u got the story then tell me what MTA is better sendmail, postfix and some instructions on HOW TO INSTALL and CONFIGURE it. And after configuring the How do I add the DF -H so that it will start seniding me the output on my email. Thanks in advance.

  Read the article

• What C++ libraries can be used in game development [closed]

  - by RedShft

  I'm currently in the planning stage for my next game, and since I've been away from C++ for a while I have some questions about helpful libraries. I plan on making a 2D game with SDL, constructing my own simple 2D engine. I plan on making this game for the PC. What libraries would you recommend to make this process easier? What about unittests? What about an enforce operator to throw exceptions? int a = 1; enforce(a == 2); //Throws an exception, Specifically, i'm looking for general purpose libraries, that implement that make my life easier (like boost). Also, a helpful library for physics/collision, AI, XML file parsing (specifically working with the Tiled map editor), and any others that you guys have used that are useful in a 2D game.

  Read the article

• Stacks in C++

  - by MarkPearl

  So some more basics… One of the things you will be taught at any college after conquering arrays is different derivatives of collections. Stack is one of the simplest of those and very useful… A stack is a LIFO (last in first out) data structure and has at least two basic method calls – push & pop. Push, “pushes” an item on the top of the stack. Pop, removes the top most item off the stack. Because all elements on a stack are of the same type, one can use an array to implement a stack or a linked list. With the array based approach, the first element in a stack would be the first element in the array, the second on the stack would be the second on the array, etc. One limitation with an array implementation of a stack is that unless the array is dynamic, one would have to have a preset max stack size (based on the bounds of the array). Linked lists is another approach that gets past this boundary by allowing you to dynamically grow or shrink a collection of data. Stacks have many applications… a typical computer science example would be Postfix Expression Calculator, where the LIFO principle is maintained.

  Read the article

• Implementation of instance testing in Java, C++, C#

  - by Jake

  For curiosity purposes as well as understanding what they entail in a program, I'm curious as to how instance testing (instanceof/is/using dynamic_cast in c++) works. I've tried to google it (particularly for java) but the only pages that come up are tutorials on how to use the operator. How do the implementations vary across those langauges? How do they treat classes with identical signatures? Also, it's been drilled into my head that using instance testing is a mark of bad design. Why exactly is this? When is that applicable, instanceof should still be used in methods like .equals() and such right? I was also thinking of this in the context of exception handling, again particularly in Java. When you have mutliple catch statements, how does that work? Is that instance testing or is it just resolved during compilation where each thrown exception would go to?

  Read the article

• Does SMTP greylisting a) stop much spam and b) stop much legitimate mail?

  - by Whisk

  I've just set up an SMTP server on a relatively little used domain using Postfix and enabled greylisting with SQLGrey. So far it seems to be working OK, and while there's the slight irritation of delays to emails from new senders, I can see from the logs that it's deterring a number of spam messages. In your experience does greylisting effectively stop much spam? Is it a useful addition to e.g. SpamAssassin or is adding it on top overkill/unnecessary? If I were to roll this out to heavier use domains (perhaps with more demanding users) would you anticipate a significant portion of poorly configured mail servers that would end up bouncing or losing messages?

  Read the article

• Null Or Empty Coalescing

  In my last blog post, I wrote about the proper way to check for empty enumerations and proposed an IsNullOrEmpty method for collections which sparked a lot of discussion. This post covers a similar issue, but from a different angle. A very long time ago, I wrote about my love for the null coalescing operator. However, over time, Ive found it to be not quite as useful as it could be when dealing with strings. For example, heres the code I might want to write: public static void DoSomething(string...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

  Read the article

• How to get the basic mail command in ubuntu 10 to work

  - by Maureen Adamson

  I am a college lecturer to whom the task of supporting the students' Linux Server has fallen. My students just need to use the mail command to communicate with me and each other. I thought mail would be there by default but it wasn't. I have tried all the advice I found on the Internet and tried to install mailutils, sendmail, mailx, exim4 and postfix. There were more but I can't remember them all now. After installing (if it works - some of them don't), when I try to send a message they all give me: /usr/sbin/sendmail: file or directory not found. I don't need anything fancy - we don't need to access remote email, just locally on our server. Incidentally the same problems are occurring on the physical server and my test virtual machine, installed at different times but both Ubuntu 10. Can anyone help me?

  Read the article

• How should a site respond to automated login attempts with phony usernames?

  - by qntmfred

  For the last couple weeks I've been seeing a consistent stream of 15-30 invalid login attempts per hours on my site. Many of them are non-sensical usernames that nobody would ever register for real, and often contain typical spam-related keywords. They all come from different IP addresses so I can't just IP block/throttle the requests. I'm not worried about unauthorized access to real accounts since they aren't using real usernames. And if it were a member of my site trying to brute force logins, they could easily scrape the valid usernames from the site, so I'm not worried about that kind of malicious behavior either. But what's the point of this type of activity? What would whichever bot operator is doing this have to gain by attempting all these logins?

  Read the article

• I installed DKIM and SPF. Do I need to install Domain Keys as well?

  - by johnlai2004

  I have linux apache mysql and php server. My website uses the php mail() function and the server's postfix server to email other people. I successfully installed SPF and DKIM on my server to reduce the likelihood of my website's email-outs from ending up in people's spam boxes. In my research, I stumbled on Domain Keys which seems to be a "historical" version of DKIM. Do the big web mail services like Google, Yahoo and Hotmail still use Domain Keys? If not, then maybe I don't need to install it?

  Read the article

• Dovecot and StartSSL problems with issuer

  - by knoim

  I am using dovecot (1) and trying to get my StartSSL certificate running. ssl_key_file points to my private key I tried pointing ssl_cert_file to my public key, with and without using the class1 certificate from http://www.startssl.com/certs/sub.class1.server.ca.pem as ssl_ca_file aswell as combing them with cat publickey sub.class1.server.ca.pem chained My mail client keeps telling me the certificate has no issuer, but doing openssl x509 on my public certificate tells me it is C=IL, O=StartCom Ltd., OU=Secure Digital Certificate Signing, CN=StartCom Class 1 Primary Intermediate Server CA My option for the CSR were: openssl req -new -newkey rsa:4096 -nodes Dovecot's log doesn't mention any problems. EDIT: Doesn't seem to be a problem with dovecot. I am having the same problem with postfix. openssl verify gives me the same error.

  Read the article

• i[Pod|Phone|Pad|*] backups in iTunes

  - by Maroloccio

  iTunes <- iPhone. At sync time, a back-up is performed. Which data is included, which data is not? i.e. are songs (potentially redundant) backed-up so that a computer ends up having both the source file on the filesystem and the copy within the device back-up? Is anything on the iPhone filesystem not backed up? (i.e. on a Mac using Time Machine, some files are excluded from the back-up even if not all of them can be recreated upon restore - I lost my postfix config this way..)

  Read the article

• nagios: trouble using check_smtps command

  - by ethrbunny

  I'm trying to use this command to check on port 587 for my postfix server. Using nmap -P0 mail.server.com I see this: Starting Nmap 5.51 ( http://nmap.org ) at 2013-11-04 05:01 PST Nmap scan report for mail.server.com (xx.xx.xx.xx) Host is up (0.0016s latency). rDNS record for xx.xx.xx.xx: another.server.com Not shown: 990 closed ports PORT STATE SERVICE 22/tcp open ssh 25/tcp open smtp 110/tcp open pop3 111/tcp open rpcbind 143/tcp open imap 465/tcp open smtps 587/tcp open submission 993/tcp open imaps 995/tcp open pop3s 5666/tcp open nrpe So I know the relevant ports for smtps (465 or 587) are open. When I use openssl s_client -connect mail.server.com:587 -starttls smtp I get a connection with all the various SSL info. (Same for port 465). But when I try libexec/check_ssmtp -H mail.server.com -p587 I get: CRITICAL - Cannot make SSL connection. 140200102082408:error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:s23_clnt.c:699: What am I doing wrong?

  Read the article

• What do you do when your naming convention clashes with your language?

  - by Jon Purdy

  Okay, this is one of those little things that always bugged me. I typically don't abbreviate identifiers, and the only time I use a short identifier (e.g., i) is for a tight loop. So it irritates me when I'm working in C++ and I have a variable that needs to be named operator or class and I have to work around it or use an abbreviation, because it ends up sticking out. Caveat: this may happen to me disproportionately often because I work a lot in programming language design, where domain objects may mirror concepts in the host language and inadvertently cause clashes. How would you deal with this? Abbreviate? (op) Misspell? (klass) Something else? (operator_)

  Read the article

• Dovecot, POP3 and Gmail

  - by Eric J.

  I setup Postfix and Dovecot on a new Ubuntu box following these directions. From a client machine, I validate that POP3 seems to be working telnet mydomain.com 110 +OK Dovecot ready. USER [email protected] +OK PASS mypassword +OK Logged in. quit +OK Logging out. However, when trying to configure Gmail on the same client to retrieve email via POP3, I get the error Server denied POP3 access for the given username and password. Server returned error: "Login failed." I carefully confirmed that Gmail is configured to use the same POP Server, Port, Username and Password I used when checking the connection with telnet. What could be causing Gmail to get a "Login failed" message?

  Read the article

• Resilient Linux Mail Server Setup

  - by Coops

  How would people design a resilient mail server setup with Linux? On an application level what the system needs to provide is both an incoming and outgoing mail service (i.e. SMTP & IMAP), along with filtering and archive storage (the archive part isn't critical yet, so we'll look at this later probably). What is required on top of this is a resilient system, i.e. one which will handle individual server failures without interrupting service. As such I would term this a High Availability mail system. This is in contrast to a High Performance mail setup, as in our case the volume of mail being handled isn't the important factor, it's simply that it stays online. Having not approached this problem before, the first thing I thought of was a clustered file system (gfs/gluster/etc), combined with heartbeat to failover a floating IP to another box in the case of a server failure. Combined with postfix & dovecot does this sound feasible to people?

  Read the article

• How to change password schema for Dovecot user authentication for an already existing mail server

  - by deb_lrnr

  Hello, I have an email server setup on Debian Lenny with Postfix, Dovecot, SASL and MySQL. Currently, the password scheme in my dovecot-sql.conf file is set to: CRYPT default_pass_scheme = CRYPT I would like to globally change the scheme to something stronger like SSHA, or MD5-CRYPT and re-hash all passwords with SSHA. What is the best way to do this? The Dovecot wiki mentions how passwords that don't follow the default scheme defined in dovecot-sql.conf can be prefixed with "{ssha}password", but I couldn't see anything regarding changing an already-existing scheme to a new one for all passwords that are already in the database. Thanks for your help!

  Read the article

• Smart Meter Management on the NetBeans Platform

  - by Geertjan

  Netinium® NCC is the operator console for the Netinium® AMM+ platform, a Head End system for multi-vendor smart meter and smart grid infrastructures. The role based NCC provides a uniform operations environment for grid operators and utilities to securely manage millions of smart meters, in-home displays and other smart devices using different types of communication networks such as IP, PLC, GPRS, CDMA and BPL. Based on the NetBeans Platform, the NCC offers the flexibility to easily extend the GUI with new functionality when new devices are added to the system.  For more information visit http://www.netinium.com.

  Read the article

• Is it bad practice to use <?= tag in PHP

  - by marco-fiset

  I've come across this PHP tag <?= ?> recently and I am reluctant to use it, but it itches so hard that I wanted to have your take on it. I know it is bad practice to use short tags <? ?> and that we should use full tags <?php ?> instead, but what about this one : <?= ?>? It would save some typing and it would be better for code readability, IMO. So instead of this: <input name="someVar" value="<?php echo $someVar; ?>"> I could write it like this, which is cleaner : <input name="someVar" value="<?= $someVar ?>"> Is using this operator frowned upon?

  Read the article

• SEO Question - allintitle with or without quotes

  - by Aaron

  I'm trying to learn more about implementing basic SEO strategies and have been spending a lot of time refining my keywords using Google Analytics combined with manually checking them using Google's allintitle operator. However, I'm unclear on whether I should be using quotes with my allintitles. Example: allintitle: seo tips and tricks for beginners 191 results allintitle: "seo tips and tricks for beginners" 70 results My thought is that it would be more accurate to use it without quotes because that way you get a more well rounded idea of all those you are competing with. So, my question is does Google give more weight to exact matches in the title tag or does that not really matter? If someone searched for: seo tips and tricks for beginners, would they be more likely to see the ones that have that exact phrase in their title tag or does that not have any impact?

  Read the article

• WPF Release History : Q1 2010 SP1 (version 2010.1.0422)

  Q1 2010 SP1 Changes: RadGrid Important Changes: The enumerator of RadGridView.Items now enumerates data items only (use RadGridView.Items.Groups to retrieve group items). What's New: Added support for BorderBrush and BorderThickness for GridViewRow. Editable field filter logical composition operator (And/Or). New overload of the GridViewDataContro.GetDistinctValues method that accepts the number of distinct values to return as a parameter. Group footer row now uses its Item as aggregate...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

  Read the article

• SSL Certificate

  - by Dremarturg

  Hey, I have a mail-server running and I want to buy a SSL-Certificate as they are pretty cheap now. I use mail.domain.com as reverse-DNS, POP3 and SMTP clients use mail.domain.com (some use pop3.domain.com and smtp.domain.com) for sending and receiving e-mails. The SSL-Submission asks me for a domain - is it mail.domain.com or domain.com as I do not have a Wildcard-SSL? I just want to use it for Mail. Or is it possible to use it for both by using domain.com? (Apache and Postfix/Courier on the same server and IP)

  Read the article

• Sources of requirements? [closed]

  - by user970696

  I was reading a book about SW engineering the other day and it went like: Sources of both functional and non-functional requirements are: law (for specific cases) business and user requirements etc. //what else then? So the question is, what other sources of requirements there are when an analyst is gathering the information? Lets consider a desktop app for mobile operator. As for the comment, I do not think this is a broad question as the books usually mention 1-2 sources. I would like to know more, if anyone can help.

  Read the article

• Introduction to JBatch

  - by reza_rahman

  It seems batch processing is moving more and more into the realm of the Java developer. In recognition of this fact, JBatch (aka Java Batch, JSR 352, Batch Applications for the Java Platform) was added to Java EE 7. In a recent article JBatch specification lead Chris Vignola of IBM provides a high level overview of the API. He discusses the core concepts/motivation, the Job Specification Language, the reader-processor-writer pattern, job operator, job repository, chunking, packaging, partitions, split/flow and the like. You can also check out the official specification yourself or try things out with the newly released Java EE 7 SDK.

  Read the article

< Previous Page | 83 84 85 86 87 88 89 90 91 92 93 94  | Next Page >