Search Results

Search found 13476 results on 540 pages for 'non lazy ptr'.

Page 130/540 | < Previous Page | 126 127 128 129 130 131 132 133 134 135 136 137  | Next Page >

  • What's a regular language?

    - by Javier Badia
    I've read that you can't parse HTML with regular expressions because HTML is not a regular language. I tried searching Wikipedia, but I didn't understand a word of what the various related articles said. Can someone explain, in simpler terms, what's a regular (or non-regular) language, and why non-regular languages can't be parsed with regexes?

    Read the article

  • Why does one loop take longer to detect a shared memory update than another loop?

    - by Joseph Garvin
    I've written a 'server' program that writes to shared memory, and a client program that reads from the memory. The server has different 'channels' that it can be writing to, which are just different linked lists that it's appending items too. The client is interested in some of the linked lists, and wants to read every node that's added to those lists as it comes in, with the minimum latency possible. I have 2 approaches for the client: For each linked list, the client keeps a 'bookmark' pointer to keep its place within the linked list. It round robins the linked lists, iterating through all of them over and over (it loops forever), moving each bookmark one node forward each time if it can. Whether it can is determined by the value of a 'next' member of the node. If it's non-null, then jumping to the next node is safe (the server switches it from null to non-null atomically). This approach works OK, but if there are a lot of lists to iterate over, and only a few of them are receiving updates, the latency gets bad. The server gives each list a unique ID. Each time the server appends an item to a list, it also appends the ID number of the list to a master 'update list'. The client only keeps one bookmark, a bookmark into the update list. It endlessly checks if the bookmark's next pointer is non-null ( while(node->next_ == NULL) {} ), if so moves ahead, reads the ID given, and then processes the new node on the linked list that has that ID. This, in theory, should handle large numbers of lists much better, because the client doesn't have to iterate over all of them each time. When I benchmarked the latency of both approaches (using gettimeofday), to my surprise #2 was terrible. The first approach, for a small number of linked lists, would often be under 20us of latency. The second approach would have small spats of low latencies but often be between 4,000-7,000us! Through inserting gettimeofday's here and there, I've determined that all of the added latency in approach #2 is spent in the loop repeatedly checking if the next pointer is non-null. This is puzzling to me; it's as if the change in one process is taking longer to 'publish' to the second process with the second approach. I assume there's some sort of cache interaction going on I don't understand. What's going on?

    Read the article

  • Is O_NONBLOCK being set a property of the file descriptor or underlying file?

    - by Daniel Trebbien
    From what I have been reading on The Open Group website on fcntl, open, read, and write, I get the impression that whether O_NONBLOCK is set on a file descriptor, and hence whether non-blocking I/O is used with the descriptor, should be a property of that file descriptor rather than the underlying file. Being a property of the file descriptor means, for example, that if I duplicate a file descriptor or open another descriptor to the same file, then I can use blocking I/O with one and non-blocking I/O with the other. Experimenting with a FIFO, however, it appears that it is not possible to have a blocking I/O descriptor and non-blocking I/O descriptor to the FIFO simultaneously (so whether O_NONBLOCK is set is a property of the underlying file [the FIFO]): #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> int main(int argc, char **argv) { int fds[2]; if (pipe(fds) == -1) { fprintf(stderr, "`pipe` failed.\n"); return EXIT_FAILURE; } int fd0_dup = dup(fds[0]); if (fd0_dup <= STDERR_FILENO) { fprintf(stderr, "Failed to duplicate the read end\n"); return EXIT_FAILURE; } if (fds[0] == fd0_dup) { fprintf(stderr, "`fds[0]` should not equal `fd0_dup`.\n"); return EXIT_FAILURE; } if ((fcntl(fds[0], F_GETFL) & O_NONBLOCK)) { fprintf(stderr, "`fds[0]` should not have `O_NONBLOCK` set.\n"); return EXIT_FAILURE; } if (fcntl(fd0_dup, F_SETFL, fcntl(fd0_dup, F_GETFL) | O_NONBLOCK) == -1) { fprintf(stderr, "Failed to set `O_NONBLOCK` on `fd0_dup`\n"); return EXIT_FAILURE; } if ((fcntl(fds[0], F_GETFL) & O_NONBLOCK)) { fprintf(stderr, "`fds[0]` should still have `O_NONBLOCK` unset.\n"); return EXIT_FAILURE; // RETURNS HERE } char buf[1]; if (read(fd0_dup, buf, 1) != -1) { fprintf(stderr, "Expected `read` on `fd0_dup` to fail immediately\n"); return EXIT_FAILURE; } else if (errno != EAGAIN) { fprintf(stderr, "Expected `errno` to be `EAGAIN`\n"); return EXIT_FAILURE; } return EXIT_SUCCESS; } This leaves me thinking: is it ever possible to have a non-blocking I/O descriptor and blocking I/O descriptor to the same file and if so, does it depend on the type of file (regular file, FIFO, block special file, character special file, socket, etc.)?

    Read the article

  • die $template->error() produces no line number

    - by Kinopiko
    In the following short program: use Template; my $template = Template->new (INCLUDE_PATH => "."); $template->process ("non-existent-file") or die $template->error (); why does "die" not produce a line number and newline? Output looks like this: $ perl template.pl file error - non-existent-file: not found ~ 503 $

    Read the article

  • Is there an Unobtrusive Captcha for web forms?

    - by KP
    What is the best unobtrusive CAPTCHA for web forms? One that does not involve a UI, rather a non-UI Turing test. I have seen a simple example of a non UI CAPTCHA like the Nobot control from Microsoft. I am looking for a CAPTCHA that does not ask the user any question in any form. No riddles, no what's in this image.

    Read the article

  • how is data stored at bit level according to "Endianness" ?

    - by bakra
    I read about Endianness and understood squat... so I wrote this main() { int k = 0xA5B9BF9F; BYTE *b = (BYTE*)&k; //value at *b is 9f b++; //value at *b is BF b++; //value at *b is B9 b++; //value at *b is A5 } k was equal to "A5 B9 BF 9F" and (byte)pointer "walk" o/p was "9F BF b9 A5" so I get it bytes are stored backwards...ok. ~ so now I thought how is it stored at BIT level... I means is "9f"(1001 1111) stored as "f9"(1111 1001)? so I wrote this int _tmain(int argc, _TCHAR* argv[]) { int k = 0xA5B9BF9F; void *ptr = &k; bool temp= TRUE; cout<<"ready or not here I come \n"< for(int i=0;i<32;i++) { temp = *( (bool*)ptr + i ); if( temp ) cout<<"1 "; if( !temp) cout<<"0 "; if(i==7||i==15||i==23) cout<<" - "; } } I get some random output even for nos. like "32" I dont get anything sensible. why ?

    Read the article

  • How does WCF RIA Services handle authentication/authorization/security?

    - by Edward Tanguay
    Since no one answered this question: What issues to consider when rolling your own data-backend for Silverlight / AJAX on non-ASP.NET server? Let me ask it another way: How does WCF RIA Services handle authentication/authorization/security at a low level? e.g. how does the application on the server determine that the incoming http request to change data is coming from a valid client and not from non-desirable source, e.g. a denial-of-service bot?

    Read the article

  • <li> titles and descriptions align across top

    - by AMC
    Not quite sure how to go about describing what it is I'm trying to achieve, so I have some screenshots.. Basically, I'd like the <h2>s all have their top edges align, as well as the <p>'s. What I currently have: What I would like to have: index.html <div id="services"> <p><span>Services</span></p> <ul> <li><h2>Identity and Logo Design</h2><p>Nulla et diam risus. Praesent vestibulum augue non purus tincidunt placerat. Sed in orci leo. Duis dignissim nibh vitae lacus placerat et posuere</p></li> <li><h2>Branding</h2><p>Nulla et diam risus. Praesent vestibulum augue non purus tincidunt placerat. Sed in orci leo. Duis dignissim nibh vitae lacus placerat et posuere</p></li> <li><h2>Web Design and Development</h2><p>Nulla et diam risus. Praesent vestibulum augue non purus tincidunt placerat. Sed in orci leo. Duis dignissim nibh vitae lacus placerat et posuere</p></li> <li><h2>Social Media</h2><p>Nulla et diam risus. Praesent vestibulum augue non purus tincidunt placerat. Sed in orci leo. Duis dignissim nibh vitae lacus placerat et posuere</p></li> </ul> <div class="next"> <a href="#"><img src="img/next.png" alt="Click for more information" /></a> </div><!-- end next --> </div><!-- end services --> style.css #services { border-top: 1px solid #202020; padding-bottom: 60px; padding-top: 40px; } #services p span { font-family: nevis-webfont; font-size: 112.5%; font-weight: normal; letter-spacing: 1px; text-transform: uppercase; } #services ul li { display: inline-block; padding-left: 100px; width: 160px; } #services ul li:first-child { padding-left: 0px; } #services ul li h2 { padding-top: 20px; text-align: center; } #services .next { float: right }

    Read the article

  • Another C question

    - by maddy
    Hi all, I have a piece of code shown below #include <stdio.h> #include <stdlib.h> void Advance_String(char [2],int ); int Atoi_val; int Count22; int Is_Milestone(char [2],int P2); char String[2] = "00"; main() { while(1) { if(Is_Milestone(S,21==1) { if(atoi(S)==22) { Count_22 = Count_22 + 1; } } Atoi_val = atoi(S); Advance_String(S,Atoi_val); } } int Is_Milestone(char P1[2],int P2) { int BoolInit; char *Ptr = P1; int value = atoi(Ptr); BoolInit = (value > P2); return BoolInit; } void Advance_String(char P1[2],int Value) { if(Value!=7) { P1[1] = P1[1]+1; } else { P1[1] = '0'; P1[0] = P1[0]+1 ; } } Now my problem is Count22 never increments as the char increments never achieves the value 21 or above.Could anyone please tell me the reason for this unexpected behaviour?My question here is to find the value of Count22.Is there any problem with the code? Thanks and regards Maddy

    Read the article

  • How do determine what is *really* causing your compiler error

    - by ML
    Hi All, I am porting a very large code base and I am having more difficulty with old code. For example, this causes a compiler error: inline CP_M_ReferenceCounted * FrAssignRef(CP_M_ReferenceCounted * & to, CP_M_ReferenceCounted * from) { if (from) from->AddReference(); if (to) to->RemoveReference(); to = from; return to; } The error is: error: expected initializer before '*' token. How do I know what this is. I looked up inline member functions to be sure I understood and I dont think the inlining is the cause but I am not sure what is. Another example: template <class eachClass> eachClass FrReferenceIfClass(FxRC * ptr) { eachClass getObject = dynamic_cast<eachClass>(ptr); if (getObject) getObject->AddReference(); return getObject; } The error is: error: template declaration of 'eachClass FrReferenceIfClass' That is all. How do I decide what this is?. I am admittedly rusty with templates.

    Read the article

  • Simple dynamic memory allocation bug.

    - by M4design
    I'm sure you (pros) can identify the bug's' in my code, I also would appreciate any other comments on my code. BTW, the code crashes after I run it. #include <stdlib.h> #include <stdio.h> #include <stdbool.h> typedef struct { int x; int y; } Location; typedef struct { bool walkable; unsigned char walked; // number of times walked upon } Cell; typedef struct { char name[40]; // Name of maze Cell **grid; // 2D array of cells int rows; // Number of rows int cols; // Number of columns Location entrance; } Maze; Maze *maz_new() { int i = 0; Maze *mazPtr = (Maze *)malloc(sizeof (Maze)); if(!mazPtr) { puts("The memory couldn't be initilised, Press ENTER to exit"); getchar(); exit(-1); } else { // allocating memory for the grid mazPtr->grid = (Cell **) malloc((sizeof (Cell)) * (mazPtr->rows)); for(i = 0; i < mazPtr->rows; i++) mazPtr->grid[i] = (Cell *) malloc((sizeof (Cell)) * (mazPtr->cols)); } return mazPtr; } void maz_delete(Maze *maz) { int i = 0; if (maz != NULL) { for(i = 0; i < maz->rows; i++) free(maz->grid[i]); free(maz->grid); } } int main() { Maze *ptr = maz_new(); maz_delete(ptr); getchar(); return 0; } Thanks in advance.

    Read the article

  • generated service mock: everything but RhinoMocks fails?

    - by hko
    I have the "quest" to search for the next Mocking Framework for my company, and basically it's down to NSubstitute (simplest syntax, but no strict mocks), FakeItEasy(best reviews, Roy Osherove bonus, and slightly better lib support than NSubstitute), Moq (best "other libs support", biggest featureset, downside: mock.Object). We definitely want to move on from RhinoMocks, e.g. because of the unusefull interactiontest error messages (it should tell me what the parameter was instead, when a verification fails). So I was pretty surprised the other day (that was yesterday) when I found out RhinoMocks could do a thing where every other mock framework fails at: Mocking an autogenerated SomethingService (a typical VS autogenerated service with a default construtor in a partial class). Please don't argue about the design.. I intend to write lightweight integration tests (and some unit tests), and I can't mess around with the service, the product is installed on too many customers system. See this code: // here the NSubstitute and FakeItEasy equivalents throw an exception.. see below TicketStoreService fakeTicketStoreService = MockRepository.GenerateMock<TicketStoreService>(); fakeTicketStoreService.Expect(service => service.DoSomething(Arg.Is(new Guid())).Return(new Guid()); fakeTicketStoreService.DoSomething(Arg.Is(new Guid())); fakeTicketStoreService.VerifyAllExpectations(); Note that DoSomething is a non-virtual methodcall in an autogenerated class. So it shouldn't work, according to common knowledge. But it does. Problem is that it's the only (non commercial) framework that can do this: Rhino.Mocks works, and verification works too FakeItEasy says it doesn't find a default constructor (probably just wrong exception message): No default constructor was found on the type SomeNamespace.TicketStoreService Moq gives something sane and understandable: Invalid setup on a non-virtual (overridable in VB) member: service=> service.DoSomething Nsubstitute gives a message System.NotSupportedException: Cannot serialize member System.ComponentModel.Component.Site of type System.ComponentModel.ISite because it is an interface. I'm really wondering what's going on here with the frameworks, except Moq. The "fancy new" frameworks seem to have an initial perf hit too, probably preparing some Type cache and serializing stuff, whilst RhinoMocks somehow manages to create a very "slim" mock without recursion. I have to admit I didn't like RhinoMocks very well, but here it shines.. unfortunately. So, is there a way to get that to work with newer (non-commercial!) mocking frameworks, or somehow get a sane error message out of Rhino.Mocks? And why can Rhino.Mocks achieve this, when clearly every Mocking framework states it can only work with virtual methods when given a concrete class? Let's not derail the discussion by talking about alternative approaches like Extract&Override or runtime-proxy Mocking frameworks like JustMock/TypeMock/Moles or the new Fakes framework, I know these, but that would be less ideal solutions, for reasons beyond this topic. Any help appreciated..

    Read the article

  • Regular expression to validate name n language other then english like Spanish..

    - by BT
    Hi, how can i write a regular expression to validate name field in a multilingual web application, i want to validate the name field for non-English languages e.g. Spanish or German, and we need to make sure that no one enter digits or special characters. I'm using .NET. I believe we can't use expression as below for non-English language. ^[a-zA-Z]{1,20}$ Any help will be highly appreciated!

    Read the article

  • Applying Microsoft Management Console Policies

    - by Hipno
    Hello, I am using windows 7. i got a user on my computer a non-admin user, and i want to apply on him user policies from the Microsoft Management Console. i added group policy object editor, chose Non-admin group, set a setting, saved and close. but i when i logon to that user i applied to, it just won't effect! please tell me what i miss, thank you.

    Read the article

  • Some clarification on rvalue references

    - by Dennis Zickefoose
    First: where are std::move and std::forward defined? I know what they do, but I can't find proof that any standard header is required to include them. In gcc44 sometimes std::move is available, and sometimes its not, so a definitive include directive would be useful. When implementing move semantics, the source is presumably left in an undefined state. Should this state necessarily be a valid state for the object? Obviously, you need to be able to call the object's destructor, and be able to assign to it by whatever means the class exposes. But should other operations be valid? I suppose what I'm asking is, if your class guarantees certain invariants, should you strive to enforce those invariants when the user has said they don't care about them anymore? Next: when you don't care about move semantics, are there any limitations that would cause a non-const reference to be preferred over an rvalue reference when dealing with function parameters? void function(T&); over void function(T&&); From a caller's perspective, being able to pass functions temporary values is occasionally useful, so it seems as though one should grant that option whenever it is feasible to do so. And rvalue references are themselves lvalues, so you can't inadvertently call a move-constructor instead of a copy-constructor, or something like that. I don't see a downside, but I'm sure there is one. Which brings me to my final question. You still can not bind temporaries to non-const references. But you can bind them to non-const rvalue references. And you can then pass along that reference as a non-const reference in another function. void function1(int& r) { r++; } void function2(int&& r) { function1(r); } int main() { function1(5); //bad function2(5); //good } Besides the fact that it doesn't do anything, is there anything wrong with that code? My gut says of course not, since changing rvalue references is kind of the whole point to their existence. And if the passed value is legitimately const, the compiler will catch it and yell at you. But by all appearances, this is a runaround of a mechanism that was presumably put in place for a reason, so I'd just like confirmation that I'm not doing anything foolish.

    Read the article

  • Control Reference Static Method Performance

    - by dotnetguts
    I have just asked which one is better? Static Vs Non-Static? http://stackoverflow.com/questions/3016717/static-vs-non-static-method-performance-c I would like to take this discussion one step ahead. Consider If i pass reference of Panel control as parameter to Public static method, will static method still rules in performance?

    Read the article

  • activemodel for rails < 3

    - by brad
    Does anyone know if activemodel works with 2.3.5? I'm looking for this exact functionality (namely, validations for non-AR objects) and I'm trying to find a clean solution for a Rails 2.3.5 app. Or if anyone knows of a good gem/plugin to use that can mimic activerecord like validations for non AR objects, I'm all ears

    Read the article

  • C Programing - Return libcurl http response to string to the calling function

    - by empty set
    I have a homework and i need somehow to compare two http responses. I am writing it on C (dumb decision) and i use libcurl to make things easier. I am calling the function that uses libcurl to http request and response from another function and i want to return the http response to it. Anyway, the code below doesn't work, any ideas? #include <stdio.h> #include <curl/curl.h> #include <string.h> size_t write_data(void *ptr, size_t size, size_t nmemb, void *stream) { size_t written; written = fwrite(ptr, size, nmemb, stream); return written; } char *handle_url(void) { CURL *curl; char *fp; CURLcode res; char *url = "http://www.yahoo.com"; curl = curl_easy_init(); if (curl) { curl_easy_setopt(curl, CURLOPT_URL, url); curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data); curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp); res = curl_easy_perform(curl); if(res != CURLE_OK) fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res)); curl_easy_cleanup(curl); //printf("\n%s", fp); } return fp; } This solution C libcurl get output into a string works, but not in my case because i want to return this string to the calling function.

    Read the article

  • Scroll event of jquery is not working in IE 7 with IE 7 standard but works in IE8,9

    - by SidP
    I have an example below which has a terms div which has some terms and conditions as content. When the user scroll the div to bottom, then the checkbox is enabled. This is only not working only in IE 7 with IE 7/8/9 standards (I am changing the standard options from Developer window). Following is my html, css and js: <body> <div id="terms">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer lacinia dui vel velit bibendum cursus. Nunc eget lacus vitae nulla euismod elementum ornare ac urna. Nam enim est, bibendum eu ultricies eu, mollis vitae lacus. Duis porta vulputate feugiat. Nullam eu iaculis lacus. Aliquam adipiscing posuere consequat. Donec et dui non massa congue eleifend. Nunc tortor diam, luctus eget mollis sit amet, posuere nec lectus. Morbi sit amet ultricies nisi. Nam sodales quam non mi tristique sollicitudin. Vestibulum vel augue eget mi tincidunt commodo. Sed egestas metus nibh, et vestibulum augue. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer lacinia dui vel velit bibendum cursus. Nunc eget lacus vitae nulla euismod elementum ornare ac urna. Nam enim est, bibendum eu ultricies eu, mollis vitae lacus. Duis porta vulputate feugiat. Nullam eu iaculis lacus. Aliquam adipiscing posuere consequat. Donec et dui non massa congue eleifend. Nunc tortor diam, luctus eget mollis sit amet, posuere nec lectus. Morbi sit amet ultricies nisi. Nam sodales quam non mi tristique sollicitudin. Vestibulum vel augue eget mi tincidunt commodo. Sed egestas metus nibh, et vestibulum augue. </div> <input type="checkbox" name="cb1" id="cb1" disabled="true" /> </body> CSS: <style type="text/css"> #terms { height: 100px; overflow: auto; } body{ width:960px; margin: 0 auto; } </style> JS: <script src="jquery-1.8.1.js"></script> <script type="text/javascript">//<![CDATA[ $(window).load(function(){ $('#terms').scroll(function() { if ($(this)[0].scrollHeight - $(this).scrollTop() == $(this).outerHeight()) { $("#cb1").removeAttr("disabled"); } else { $("#cb1").attr("disabled", "true"); } }); });//]]> </script>

    Read the article

  • Endianness and C API's: Specifically OpenSSL.

    - by Hassan Syed
    I have an algorithm that uses the following OpenSSL calls: HMAC_update() / HMAC_final() // ripe160 EVP_CipherUpdate() / EVP_CipherFinal() // cbc_blowfish These algorithm take a unsigned char * into the "plain text". My input data is comes from a C++ std::string::c_str() which originate from a protocol buffer object as a encoded UTF-8 string. UTF-8 strings are meant to be endian neutrial. However I'm a bit paranoid about how OpenSSL may perform operations on the data. My understanding is that encryption algorithms work on 8-bit blocks of data, and if a unsigned char * is used for pointer arithmetic when the operations are performed the algorithms should be endian neutral and I do not need to worry about anything. My uncertainty is compounded by the fact that I am working on a little-endian machine and have never done any real cross-architecture programming. My beliefs/reasoning are/is based on the following two properties std::string (not wstring) internally uses a 8-bit ptr and a the resulting c_str() ptr will itterate the same way regardless of the CPU architecture. Encryption algorithms are either by design, or by implementation, endian neutral. I know the best way to get a definitive answer is to use QEMU and do some cross-platform unit tests (which I plan to do). My question is a request for comments on my reasoning, and perhaps will assist other programmers when faced with similar problems.

    Read the article

< Previous Page | 126 127 128 129 130 131 132 133 134 135 136 137  | Next Page >