Search Results

Search found 15377 results on 616 pages for 'socket programming'.

Page 3/616 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • Programming Constructs History

    - by kunjaan
    I need some help in figuring out which language introduced the constructs that we use everyday. For example: Constructs Introduced from LISP If-Else Block :"The ubiquitous if-then-else structure, now taken for granted as an essential element of any programming language, was invented by McCarthy for use in Lisp, where it saw its first appearance in a more general form (the cond structure). It was inherited by Algol, which popularized it. " - WikiPedia Function Type : Functions as first class citizens. Garbage Collection

    Read the article

  • Reading / Writing from a Unix Socket in Ruby

    - by Olly
    I'm trying to connect, read and write from a UNIX socket in Ruby. It is a stats socket used by haproxy. My code is the following: require 'socket' socket = UNIXSocket.new("/tmp/haproxy.stats.socket") # First attempt: works socket.puts("show stat") while(line = socket.gets) do puts line end # Second attemp: fails socket.puts("show stat") while(line = socket.gets) do puts line end It succeeds the first time, but on the second attempt fails. I'm not sure why. # pxname,svname,qcur,qmax,scur,smax,slim,stot,bin,bout,dreq,dresp,ereq,econ,eresp,wretr,wredis,status,weight,act,bck,chkfail,chkdown,lastchg,downtime,qlimit,pid,iid,sid,throttle,lbtot,tracked,type,rate,rate_lim,rate_max,check_status,check_code,check_duration,hrsp_1xx,hrsp_2xx,hrsp_3xx,hrsp_4xx,hrsp_5xx,hrsp_other,hanafail,req_rate,req_rate_max,req_tot,cli_abrt,srv_abrt, stats,FRONTEND,,,0,0,2000,0,0,0,0,0,0,,,,,OPEN,,,,,,,,,1,1,0,,,,0,0,0,0,,,,0,0,0,0,0,0,,0,0,0,,, stats,BACKEND,0,0,0,0,2000,0,0,0,0,0,,0,0,0,0,UP,0,0,0,,0,22,0,,1,1,0,,0,,1,0,,0,,,,0,0,0,0,0,0,,,,,0,0, legacy_socket,FRONTEND,,,0,0,1000,0,0,0,0,0,0,,,,,OPEN,,,,,,,,,1,2,0,,,,0,0,0,0,,,,0,0,0,0,0,0,,0,0,0,,, all,FRONTEND,,,0,0,10000,0,0,0,0,0,0,,,,,OPEN,,,,,,,,,1,3,0,,,,0,0,0,0,,,,0,0,0,0,0,0,,0,0,0,,, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,1,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,2,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,3,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,4,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,5,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,6,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,22,22,,1,4,7,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,21,21,,1,4,8,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,21,21,,1,4,9,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,socket,0,0,0,0,200,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,21,21,,1,4,10,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, socket_backend,BACKEND,0,0,0,0,0,0,0,0,0,0,,0,0,0,0,DOWN,0,0,0,,1,21,21,,1,4,0,,0,,1,0,,0,,,,0,0,0,0,0,0,,,,,0,0, api_backend,api,0,0,0,0,200,0,0,0,,0,,0,0,0,0,UP,1,1,0,0,0,22,0,,1,5,1,,0,,2,0,,0,L4OK,,0,0,0,0,0,0,0,0,,,,0,0, api_backend,api,0,0,0,0,1,0,0,0,,0,,0,0,0,0,UP,1,1,0,0,0,22,0,,1,5,2,,0,,2,0,,0,L4OK,,0,0,0,0,0,0,0,0,,,,0,0, api_backend,api,0,0,0,0,1,0,0,0,,0,,0,0,0,0,DOWN,1,1,0,0,1,21,21,,1,5,3,,0,,2,0,,0,L4CON,,0,0,0,0,0,0,0,0,,,,0,0, api_backend,BACKEND,0,0,0,0,0,0,0,0,0,0,,0,0,0,0,UP,2,2,0,,0,22,0,,1,5,0,,0,,1,0,,0,,,,0,0,0,0,0,0,,,,,0,0, www_backend,ruby-www,0,0,0,0,10000,0,0,0,,0,,0,0,0,0,UP,1,1,0,0,0,22,0,,1,6,1,,0,,2,0,,0,L4OK,,0,0,0,0,0,0,0,0,,,,0,0, www_backend,BACKEND,0,0,0,0,0,0,0,0,0,0,,0,0,0,0,UP,1,1,0,,0,22,0,,1,6,0,,0,,1,0,,0,,,,0,0,0,0,0,0,,,,,0,0, /Users/Olly/Desktop/haproxy_stats.rb:14:in `write': Broken pipe (Errno::EPIPE) from /Users/Olly/Desktop/haproxy_stats.rb:14:in `puts' from /Users/Olly/Desktop/haproxy_stats.rb:14 What is the problem? Is there a good reference to using UNIX sockets and Ruby?

    Read the article

  • what is the difference between declarative and imperative programming

    - by Brad
    I have been searching the web looking for a definition for declarative and imperative programming that would shed some light for me. However the language used at some of the resources that I have found is daunting - for instance at wikipedia. Does any one have a real world example that they could show me that might bring some perspective to this subject...perhaps in c# thanks

    Read the article

  • Tellago && Tellago Studios 2010

    - by gsusx
    With 2011 around the corner we, at Tellago and Tellago Studios , we have been spending a lot of times evaluating our successes and failures (yes those too ;)) of 2010 and delineating some of our goals and strategies for 2011. When I look at 2010 here are some of the things that quickly jump off the page: Growing Tellago by 300% Launching a brand new company: Tellago Studios Expanding our customer base Establishing our business intelligence practice http://tellago.com/what-we-say/events/business-intelligence...(read more)

    Read the article

  • Is there a "golden ratio" in coding?

    - by badallen
    My coworkers and I often come up with silly ideas such as adding entries to Urban Dictionary that are inappropriate but completely make sense if you are a developer. Or making rap songs that are about delegates, reflections or closures in JS... Anyhow, here is what I brought up this afternoon which was immediately dismissed to be a stupid idea. So I want to see if I can get redemptions here. My idea is coming up with a Golden Ratio (or in the neighborhood of) between the number of classes per project versus the number of methods/functions per class versus the number of lines per method/function. I know this is silly and borderline, if not completely, useless, but just think of all the legacy methods or classes you have encountered that are absolutely horrid - like methods with 10000 lines or classes with 10000 methods. So Golden Ratio, anyone? :)

    Read the article

  • Python: unix socket -> broken pipe

    - by Heinrich Schmetterling
    I'm trying to get Python socket working as an alternative to calling the command line socat. This socat command works fine: echo 'cmd' | sudo socat stdio <path-to-socket> but when I run this python code, I get an error: >>> import socket >>> s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) >>> s.connect(<path-to-socket>) >>> s.send('cmd') Traceback (most recent call last): File "<stdin>", line 1, in <module> socket.error: (32, 'Broken pipe') Any ideas what the issue is? Thanks.

    Read the article

  • When/Why ( if ever ) should i think about doing Generic Programming/Meta Programming

    - by hotadvice
    Hi there IMHO to me OOPS, design patterns make sense and i have been able to apply them practically. But when it comes to "generic programming /meta programming" of the Modern C++ kind, i am left confused. -- Is it a new programming/design paradigm ? -- Is it just limited to "library development"? If not, What design/coding situations call for using meta programming/generic programming. -- Does using templates mean i am doing generic programming? I have googled a lot on this topic but do not grasp the BIG PICTURE fully. Also see this post. After reading dicussions here under, up till now, I am sure ( might still not be correct): a) Generic programming and meta programming are two different concepts.

    Read the article

  • Sniff UNIX domain socket

    - by gonvaled
    I know that some process is writing to a certain unix domain socket (/var/run/asterisk/asterisk.ctl), but I do not known the pid of the sender. How can I find out who is writing to the socket? I have tried with: sudo lsof /var/run/asterisk/asterisk.ctl but it just list the owner of the socket. I would like to know who is writing / reading to this socket, and I would also like to sniff the data. Is this possible?

    Read the article

  • Is the “jQuery programming style” a kind of Reactive programming?

    - by Peter Krauss
    jQuery is a Javascript library and framework, but when we are programming with jQuery into DOM problems/solutions, we can practice a style quite different of programming... We can read about jQuery at Wikipedia, The set of jQuery core features — DOM element selections, traversal and manipulation —, enabled by its selector engine (...), created a new "programming style", fusing algorithms and DOM-data-structures This question is similar to the "subquestion-3" of this question but not so generic. The focus here is about this new kind of "programming style"... So, the question: Is the "jQuery programming style in DOM context" a new paradign? Or it is more one example of reactive programming (not "cell-oriented" but "DOM-node oriented") or another one? We have no "standard taxonomy of paradigms", so, please, in your answer, indicate also your "best choice for Wikipedia Paradign". Example: if you understand that "jQuery programming DOM" is like "awk filtering data", your choice can be event-driven.

    Read the article

  • what exactly is system programming?

    - by kentjh
    I have never understood what system programming meant. The usual definition given is "...doing something close to the Os or extending Os features...". Does using Windows API directly rather than some libraries to say do file i/o make it system programming? Was writing Android OS system programming? If I write something that would expose linux kernel through a console like app on Android am I doing system programming? If I am writing software to control a washing machine am I writing system programming? I am a beginner in programming and this is confusing me to no end. Please explain contrasting it with "application programming".

    Read the article

  • Which is the next dominant programming paradigm? [closed]

    - by Kugathasan Abimaran
    What is the next programming paradigm when OOP get lost in the market? Or else will OOP be for ever? What is your advise for the future developers? To which paradigm should we aware of? Because, before OOP, structured programming paradigm is there with C. Don't close it Please, because I need to aware, which paradigm have the ability to withstand in future? Aspect-oriented programming. Declarative programming. Functional programming. Object-oriented programming. Any Others? This describes programming paradigm according to their kernel language.

    Read the article

  • Socket read() hangs for a while when there is no data to read.

    - by janesconference
    Hi' I'm writing a simple http port forwarder. I read data from port 80, and pass the data to my lighttpd server, on port 8080. As long as I write() data on the socket on port 8080 (forwarding the request) there's no problem, but when I read() data from that socket (forwarding the response), the last read() hangs a lot (about 1 or 2 seconds) before realizing there's no more data and returning 0. I tried to set the socket to non-blocking, but this doesn't work, as sometimes it returns EWOULDBLOCKING even if there's some data left (lighttpd + cgi can be quite slow). I tried to set a timeout with select(), but, as above, a slow cgi could timeout the socket when there's actually some data to transmit. How would you do?

    Read the article

  • how a pure functional programming language manage without assignment statements?

    - by Gnijuohz
    When reading the famous SICP,I found the authors seem rather reluctant to introduce the assignment statement to Scheme in Chapter 3.I read the text and kind of understand why they feel so. As Scheme is the first functional programming language I ever know something about,I am kind of surprised that there are some functional programming languages(not Scheme of course) can do without assignments. Let use the example the book offers,the bank account example.If there is no assignment statement,how can this be done?How to change the balance variable?I ask so because I know there are some so-called pure functional languages out there and according to the Turing complete theory,this must can be done too. I learned C,Java,Python and use assignments a lot in every program I wrote.So it's really an eye-opening experience.I really hope someone can briefly explain how assignments are avoided in those functional programming languages and what profound impact(if any) it has on these languages. The example mentioned above is here: (define (make-withdraw balance) (lambda (amount) (if (>= balance amount) (begin (set! balance (- balance amount)) balance) "Insufficient funds"))) This changed the balance by set!.To me it looks a lot like a class method to change the class member balance. As I said,I am not familiar with functional programming languages,so if I said something wrong about them,feel free to point out.

    Read the article

  • Make a socket as a user but make it readable and writable by another

    - by user1598585
    I have a software that is run under user A, this software creates a socket in /sockets and the socket should be readable and writable by user B. I have tried setting the directory to have ownership A:A or A:B but when user A creates the socket, it ends up with uid A and gid A. Using ACLs has not helped so far, the default mask is preventing the rights to be effective. rw permisions for B will always turn into jusr r. If what I make is not a socket it will work fine. How can I best accomplish this task? (It is for a web-server where the web-application makes the socket and the web-server software forwards requests to it)

    Read the article

  • Make a socket as an user but make it readable and writable by another

    - by user1598585
    I have a software that is run under user A, this software creates a socket in /sockets and the socket should be readable and writable by user B. I have tried setting the directory to have ownership A:A or A:B but when user A creates the socket, it ends up with uid A and gid A. Using ACLs has not helped so far, the default mask is preventing the rights to be effective. rw permisions for B will always turn into jusr r. If what I make is not a socket it will work fine. How can I best accomplish this task? (It is for a web-server where the web-application makes the socket and the web-server software forwards requests to it)

    Read the article

  • Should functional programming be taught before imperative programming?

    - by Zifre
    It seems to me that functional programming is a great thing. It eliminates state and makes it much easier to automatically make code run in parallel. Many programmers who were first taught imperative programming styles find it very difficult to learn functional programming, because it is so different. I began to wonder if programmers who were taught functional programming first would find it hard to begin imperative programming. It seems like it would not be as hard as the other way around, so I thought it would be a good thing if more programmers were taught functional programming first. So, my question is, should functional programming be taught in school before imperative, and if so, why is it not more common to start with it?

    Read the article

  • How to join the World of Programming? [closed]

    - by litebread
    Name's Vlad and I am currently on my third year of Community College, studying Computer Science with emphasis on Programming in C++ and Networking. I have completed a few programming courses with general ease, but have not gained advanced understanding of programming through school. None of my friends are serious programmers working in the industry. Being an active lurker on many programming websites, and in general tech oriented sites I have noticed how little I know about the industry, the lingo and terminology. (I have no clue how Git hub works, but I generally understand what its for). So I am looking for help as to where I should look for information on the programming world and the industry in which I a very interested. By that I mean, what sites I should utilize to gain information on programming practices, introduction to advanced C++ and resources that simply introduce a 20some programming noob. I like programming, but I haven't dug my hands deep into it yet, I want to start to do so before I transfer to a University. All in all, where do I find information on becoming an actual programmer (Information that lays out a path). Thank you for reading. Have a great day!

    Read the article

  • Writing to Socket outputStream w/o closing it

    - by Eyal
    Hi, I'd like to write some messages to the server. Each time, for the tramsmitting only, I'm closing the outputStream and reopen it when I have to send the next message. os.write(msgBytes); os.write("\r\n".getBytes()); os.flush(); os.close(); How Can I keep this Socket's OutputStream, os, open and still be able to send the message? Thanks.

    Read the article

  • TcpListener Socket still active after program exits.

    - by lnical
    I'm trying to stop a TCP Listener as my program is exiting. I do not care about any data that is currently active on the socket or any of the active client sockets. The socket clean up code is essentially: try { myServer.Server.Shutdown(SocketShutdown.Both) } catch (Exception ex) { LogException(ex) } myServer.Server.Close(0) myServer.Stop() myServer is a TCPListener On some occasions, Shutdown will thrown an exception System.Net.Sockets.SocketException: A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied at System.Net.Sockets.Socket.Shutdown(SocketShutdown how) When this happens, the socket is never released. Even after the application exits netstat shows the socket is still in the listening state. I have not been able to create definitive reproduction scenerio, it happens at seemingly random times. Client Sockets are cleaned up independently. Do you have any suggestions to help me make this socket die?

    Read the article

  • how to bind/connect multiple UDP socket

    - by nicboul
    My initial UDP socket is binded to 127.0.0.1:9898. The first time that I get notified of incoming data by epoll/kqueue, I do recvfrom() and I fill a struct sockaddr called peer_name that contain the peer informations (ip:port). Then I create a new UPD socket using socket(), then I bind() this newly created socket to the same ip:port (127.0.0.1:9898) than my original socket. then I connect my newly created socket using connect() to the peer who just sent me something. I have the information in the struct sockaddr called peer_name. I then add my newly created socket in my epoll/kqueue vector and wait for notification. I would expect to ONLY receive UDP frame from the peer i'm ""connected to"". 1/ does netstat -a -p udp is suppose to show me the IP:PORT of the peer my newly created socket is ""connected to"" ? 2/ I'm probably doing something wrong since after creating my new socket, this socket receive all incoming UDP packets destinated to the IP:PORT I'm binded to, regardless of the source peer IP:PORT. I would like to see a working example of what I'm trying to do :) or any hint on what I'm doing wrong. thanks!

    Read the article

  • Socket send recv functions

    - by viswanathan
    I have created a socket using the following lines of code. Now i change the value of the socket i get like this m_Socket++; Even now the send recv socket functions succeeds without throwing SOCKET_ERROR. I expect that it must throw error. Am i doing something wrong. struct sockaddr_in ServerSock; // Socket address structure to bind the Port Number to listen to char *localIP ; SOCKET SocServer; //To Set up the sockaddr structure ServerSock.sin_family = AF_INET; ServerSock.sin_addr.s_addr = INADDR_ANY; ServerSock.sin_port = htons(pLantronics->m_wRIPortNo); // To Create a socket for listening on wPortNumber if(( SocServer = socket( AF_INET, SOCK_STREAM, 0 )) == INVALID_SOCKET ) { return FALSE; } //To bind the socket with wPortNumber if(bind(SocServer,(sockaddr*)&ServerSock,sizeof(ServerSock))!=0) { return FALSE; } // To Listen for the connection on wPortNumber if(listen(SocServer,SOMAXCONN)!=0) { return FALSE; } // Structure to get the IP Address of the connecting Entity sockaddr_in insock; int insocklen=sizeof(insock); //To accept the Incoming connection on the wPortNumber pLantronics->m_Socket=accept(SocServer,(struct sockaddr*)&insock,&insocklen); if(pLantronics->m_Socket == INVALID_SOCKET) { shutdown(SocServer, 2 ); closesocket(SocServer ); return FALSE; } // To make socket non-blocking DWORD dwNonBlocking = 1; if(ioctlsocket( pLantronics->m_Socket, FIONBIO, &dwNonBlocking )) { shutdown(pLantronics->m_Socket, 2); closesocket(pLantronics->m_Socket); return FALSE; } pLantronics->m_sModemName = inet_ntoa(insock.sin_addr); Now i do m_Socket++;//change to some other number ideally expecting send recv to fail. Even now the send recv socket functions succeeds without throwing SOCKET_ERROR. I expect that it must throw error. Am i doing something wrong.

    Read the article

  • What could be my path? Networking, programming, or something else?

    - by momong
    Well first and foremost, I would like to give my brief description: I was an aviation student but I didn't pursue that path because I lost my interest. Now I'm an I.T. student and currently stopped schooling because of confusion. I don't know which path I should choose: could it be programming or networking? Someone told me that on networking the money is easy, the job is easy. Others told me that programming is best suited for me because I'm very skilled and excellent at figures. I want to chose networking, but I can't find my passion for it, my mind tells me but my heart doesn't... and on programming, I don't know which language I should pick or if I like it or not. A good mentor, even if only online, would be a very big plus to me, but I don't think if there are many who could spent their time on teaching a nobody... but I'm very eager to learn. My real passion is gaming! I want to work in the gaming industry, I want to be a man behind those games! I've been a gamer freak since birth. But I don't know how to get in to that industry. I don't know what to do. I don't know which path would really suit me. Sorry if some of you find this a pointless question, but please bear with me, this could be the turn of my life.

    Read the article

  • First languages with generic programming support

    - by oluies
    Which was the first language with generic programming support, and what was the first major staticly typed language (widely used) with generics support. Generics implement the concept of parameterized types to allow for multiple types. The term generic means "pertaining to or appropriate to large groups of classes." I have seen the following mentions of "first": First-order parametric polymorphism is now a standard element of statically typed programming languages. Starting with System F [20,42] and functional programming lan- guages, the constructs have found their way into mainstream languages such as Java and C#. In these languages, first-order parametric polymorphism is usually called generics. From "Generics of a Higher Kind", Adriaan Moors, Frank Piessens, and Martin Odersky Generic programming is a style of computer programming in which algorithms are written in terms of to-be-specified-later types that are then instantiated when needed for specific types provided as parameters. This approach, pioneered by Ada in 1983 From Wikipedia Generic Programming

    Read the article

  • Programming Language, Turing Completeness and Turing Machine

    - by Amumu
    A programming language is said to be Turing Completeness if it can successfully simulate a universal TM. Let's take functional programming language for example. In functional programming, function has highest priority over anything. You can pass functions around like any primitives or objects. This is called first class function. In functional programming, your function does not produce side effect i.e. output strings onto screen, change the state of variables outside of its scope. Each function has a copy of its own objects if the objects are passed from the outside, and the copied objects are returned once the function finishes its job. Each function written purely in functional style is completely independent to anything outside of it. Thus, the complexity of the overall system is reduced. This is referred as referential transparency. In functional programming, each function can have its local variables kept its values even after the function exits. This is done by the garbage collector. The value can be reused the next time the function is called again. This is called memoization. A function usually should solve only one thing. It should model only one algorithm to answer a problem. Do you think that a function in a functional language with above properties simulate a Turing Machines? Functions (= algorithms = Turing Machines) are able to be passed around as input and returned as output. TM also accepts and simulate other TMs Memoization models the set of states of a Turing Machine. The memorized variables can be used to determine states of a TM (i.e. which lines to execute, what behavior should it take in a give state ...). Also, you can use memoization to simulate your internal tape storage. In language like C/C++, when a function exits, you lose all of its internal data (unless you store it elsewhere outside of its scope). The set of symbols are the set of all strings in a programming language, which is the higher level and human-readable version of machine code (opcode) Start state is the beginning of the function. However, with memoization, start state can be determined by memoization or if you want, switch/if-else statement in imperative programming language. But then, you can't Final accepting state when the function returns a value, or rejects if an exception happens. Thus, the function (= algorithm = TM) is decidable. Otherwise, it's undecidable. I'm not sure about this. What do you think? Is my thinking true on all of this? The reason I bring function in functional programming because I think it's closer to the idea of TM. What experience with other programming languages do you have which make you feel the idea of TM and the ideas of Computer Science in general? Can you specify how you think?

    Read the article

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >