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  • Gtk, whether destroying GtkBuilder destroies all the screens and widgets?

    - by PP
    Hi, Question regarding GtkBuilder. When we unref builder pointer does it destroys all the screens/widgets the builder had created? if( builder_ptr ) g_object_unref(G_OBJECT(builder_ptr)); Suppose we have created one screen using Glade/XML with some 2-3 top_level windows in it gtk_builder_add_from_file(builder_ptr, "Test.glade", &error ) and generated GtkBuilder pointer (as above) so after deleting this pointer does it deletes created Windows or do we need to manually delete these windows? Thanks, PP.

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  • C++ - colon after contstructer, what does it mean?

    - by waitinforatrain
    Hi, I'd happily google this but don't know what to call it to google it. I have a piece of code here: class demo { private: unsigned char len, *dat; public: demo(unsigned char le = 5, unsigned char default) : len(le) { dat = new char[len]; for (int i = 0; i <= le; i++) dat[i] = default; } void ~demo(void) { delete [] *dat; } }; class newdemo : public demo { private: int *dat1; public: newdemo(void) : demo(0, 0) { *dat1 = 0; return 0; } }; (It's from a past exam paper and the question is to correct errors in the code so ignore errors!) My question is, what are the ": len(le) " and " : demo(0, 0)" called? Something to do with inheritence?

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  • sending input parameters to another function

    - by Pegah
    Hi everybody, I need to send the list of the input arguments to readInput function. But the compiler gives error when I call readInput function. Could you please tell me where my mistake is? bool readInput(netcorr net,int argc, char * argv[]); int main(int argc, char * const argv[]) { netcorr net; bool error=readInput(net, argc, argv); } bool readInput(netcorr &net,int argc, char * argv[]) { } thanks for your help. Pegah

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  • C# to unmanaged dll data structures interop

    - by Shane Powell
    I have a unmanaged DLL that exposes a function that takes a pointer to a data structure. I have C# code that creates the data structure and calls the dll function without any problem. At the point of the function call to the dll the pointer is correct. My problem is that the DLL keeps the pointer to the structure and uses the data structure pointer at a later point in time. When the DLL comes to use the pointer it has become invalid (I assume the .net runtime has moved the memory somewhere else). What are the possible solutions to this problem? The possible solutions I can think of are: Fix the memory location of the data structure somehow? I don't know how you would do this in C# or even if you can. Allocate memory manually so that I have control over it e.g. using Marshal.AllocHGlobal Change the DLL function contract to copy the structure data (this is what I'm currently doing as a short term change, but I don't want to change the dll at all if I can help it as it's not my code to begin with). Are there any other better solutions?

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  • Getting plane slices from array data

    - by umanga
    Greetings all, I read 3d grid data (from multiple TIF images) into a structure as follows : typedef struct VolumeData{ int nx; int ny; int nz; unsigned char *data; // size is nx*ny*nz } Now I want to get the plane slices from this 1-D grid data: eg: unsigned char* getXYPlaneStack(VolumeData *vol,int z); I could implement above function because the *data array stores image stack. But i am having difficult time implement along the other axes: unsigned char* getYZPlaneStack(VolumeData *vol,int x); and unsigned char* getXZPlaneStack(VolumeData *vol,int y); any easy algorithm for this? thanks in advance.

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  • C++ memory management of reference types

    - by Russel
    Hello, I'm still a fairly novice programmer and I have a question about c++ memory management with refence types. First of all, my understanding of reference types: A pointer is put on the stack and the actual data that the pointer points to is created and placed on the heap. Standard arrays and user defined classes are refence types. Is this correct? Second, my main question is do c and c++'s memory management mechanisms (malloc, free and new, delete) always handle this properly and free the memory that a class or array is pointing to? Does everything still work if those pointers get reassigned somehow to other objects of the same size/type on the heap? What if a class has a pointer member that points to another object? I am assuming that delete/freeing the class object doesn't free what it's member pointer points to, is that correct? Thanks all! -R

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  • Reading data from text file in C

    - by themake
    I have a text file which contains words separated by space. I want to take each word from the file and store it. So i have opened the file but am unsure how to assign the word to a char. FILE *fp; fp = fopen("file.txt", "r"); //then i want char one = the first word in the file char two = the second word in the file

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  • shop by brand name in magento

    - by Jyotiranjan
    This is brand.php file having directory local/Vilpjsc/brand/Block.I want the brand name with logo(image) sholud display on home page .But I am getting the error i.e Fatal error: Call to a member function getCollection() on a non-object in /var/www/magentodemo/app/code/local/Vilpjsc/Brand/Block/Brand.php on line 25 <?php class Vilpjsc_Brand_Block_Brand extends Mage_Core_Block_Template { public function _prepareLayout() { return parent::_prepareLayout(); } //Get Collection from Brand Controller public function getBrand() { if (!$this->hasData('brand')) { $this->setData('brand', Mage::registry('brand')); } return $this->getData('brand'); } //Get Brand Featured Collection public function getFeaturedBrand() { return $this->getBrand()->getCollection()->setPageSize(12)->addFilter('status', '1'); } public function resizeImage($img,$width=100, $height=60) { if (!file_exists("./media/brand/resized")) mkdir("./media/brand/resized", 0777); $imageResized = Mage::getBaseDir('media') . DS . "brand" . DS . "resized" . DS . $width."x".$height.$img; if (!file_exists($imageResized) && file_exists("./media/brand/" . $img)) { $imageObj = new Varien_Image("./media/brand/" . $img); $imageObj->constrainOnly(TRUE); $imageObj->keepAspectRatio(TRUE); $imageObj->keepFrame(FALSE); $imageObj->resize($width, $height); $imageObj->save($imageResized); } $newImageUrl = Mage::getBaseUrl('media')."brand/resized/".$width."x".$height.$img; return $newImageUrl; } public function getNormalBrand() { return $this->getBrand()->getCollection()->addFilter('status', '0'); } public function getBrandChar() { extract($this->getBrandKey()); return $this->getBrand()->getCollection()->saveBrandcollection($char); } //Create Alphabet navigation public function navigation() { extract($this->getBrandKey()); $alphas = range('A', 'Z'); $navigation = ""; $digitClass = ""; foreach ($alphas as $key) { if ($char == $key) $class_key = "current_char"; else $class_key=""; $navigation .= "<li class='key_item " . $class_key . "'><a href='" . Mage::getBaseUrl() . "brand/index/index/brand_key/" . $key . "'>" . $key . "</a></li>"; } if ($char == "digit") { $digitClass = "current_char"; } elseif ($char == "all") $allClass = "current_char"; $navigation = "<li class='key_item " . $digitClass . "'><a href='" . Mage::getBaseUrl() . "brand/index/index/brand_key/digit'>#</a></li>" . $navigation; return $navigation; } //Get request for brand block public function getBrandKey() { $brand_key = Mage::registry('brand_key'); if ($brand_key) { $char = $brand_key->getParam('brand_key') ? $brand_key->getParam('brand_key') : 'A'; $option_id = $brand_key->getParam('option_id') ? $brand_key->getParam('option_id') : '1'; $brand = $brand_key->getParam('brand') ? $brand_key->getParam('brand') : 'Nike'; } else { $char = 'digit'; $option_id = '544'; } return compact('char', 'option_id', 'brand'); } }

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  • use Variable on VBS

    - by Amirreza
    I Convert a reg file to VBS commands. [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run] @="" "VPService"="C:\\Windows\\System32\\VPService.exe" but i can't use %systemroot% variable instead C:\Windows\ on this. Option Explicit Dim objShell Set objShell = CreateObject("WScript.Shell") Dim strComputer, ArrOfValue, oReg const HKEY_USERS = &H80000003 const HKEY_LOCAL_MACHINE = &H80000002 const HKEY_CURRENT_USER = &H80000001 const HKEY_CLASSES_ROOT = &H80000000 strComputer = "." Set oReg=GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & strComputer & "\root\default:StdRegProv") objShell.RegWrite "HKCU\Software\Microsoft\Windows\CurrentVersion\Run\", "" objShell.RegWrite "HKCU\Software\Microsoft\Windows\CurrentVersion\Run\", "", "REG_SZ" 'Default value objShell.RegWrite "HKCU\Software\Microsoft\Windows\CurrentVersion\Run\VPService", "C:\\Windows\\System32\\VPService.exe", "REG_SZ" Set objShell = Nothing WScript.Quit how can use %systemroot% variable instead C:\Windows\ on this code?

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  • Linked lists in Java - help with assignment

    - by user368241
    Representation of a string in linked lists In every intersection in the list there will be 3 fields : The letter itself. The number of times it appears consecutively. A pointer to the next intersection in the list. The following class CharNode represents a intersection in the list : public class CharNode { private char _data; private int _value; private charNode _next; public CharNode (char c, int val, charNode n) { _data = c; _value = val; _next = n; } public charNode getNext() { return _next; } public void setNext (charNode node) { _next = node; } public int getValue() { return _value; } public void setValue (int v) { value = v; } public char getData() { return _data; } public void setData (char c) { _data = c; } } The class StringList represents the whole list : public class StringList { private charNode _head; public StringList() { _head = null; } public StringList (CharNode node) { _head = node; } } Add methods to the class StringList according to the details : (I will add methods gradually according to my specific questions) (Pay attention, these are methods from the class String and we want to fulfill them by the representation of a string by a list as explained above) public int indexOf (int ch) - returns the index in the string it is operated on of the first appeareance of the char "ch". If the char "ch" doesn't appear in the string, returns -1. If the value of fromIndex isn't in the range, returns -1. Pay attention to all the possible error cases. Write what is the time complexity and space complexity of every method that you wrote. Make sure the methods you wrote are effective. It is NOT allowed to use ready classes of Java. It is NOT allowed to move to string and use string operations. Here is my try to write the method indexOf (int ch). Kindly assist me with fixing the bugs so I can move on. public int indexOf (int ch) { int count = 0; charNode pose = _head; if (pose == null ) { return -1; } for (pose = _head; pose!=null && pose.getNext()!='ch'; pose = pose.getNext()) { count++; } if (pose!=null) return count; else return -1; }

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  • assignment not working in a dll exported C++ class

    - by Jim Jones
    Using VS 2008 Have a C++ class in which I'm calling functions from a 3rd party dll. The definition in the header file is as follows: namespace OITImageExport { class ImageExport { private: SCCERR seResult; /* Error code returned. */ VTHDOC hDoc; /* Input doc handle returned by DAOpenDocument(). */ VTHEXPORT hExport; /* Handle to the export returned by EXOpenExport(). */ VTDWORD dwFIFlags; /* Used in setting the SCCOPT_FIFLAGS option. */ VTCHAR szError[256]; /* Error string buffer. */ VTDWORD dwOutputId; /* Output Format. */ VTDWORD dwSpecType; public: ImageExport(const char* outputId, const char* specType); void ProcessDocument(const char* inputPath, const char* outputPath); ~ImageExport(); }; } In the constructor I initialize two of the class fields having values which come from enumerations in the 3rd party dll: ImageExport::ImageExport(const char* outputId, const char* specType) { if(outputId == "jpeg") { dwOutputId = FI_JPEGFIF; } if(specType == "ansi") { dwSpecType = IOTYPE_ANSIPATH; } seResult = DAInit(); if (seResult != SCCERR_OK) { DAGetErrorString(seResult, szError, sizeof(szError)); fprintf(stderr, "DAInit() failed: %s (0x%04X)\n", szError, seResult); exit(seResult); } } When I use this class inside of a console app, with a main method in another file (all in the same namespace), instantiating the class object and calling the methods, it works like a champ. So, now that I know the basic code works, I open a dll project using the class header and code file. Course I have to add the dll macro, namely: #ifdef IMAGEDLL_EXPORTS #define DLL __declspec(dllexport) #else #define DLL __declspec(dllimport) #endif and changed the class definition to "class DLL ImageExport". Compiled nicely to a dll and .lib file (No errors, No warnings). Now to test this dll I open another console project using the same main method as before and linking to the (dll) lib file. Had problems, which when tracked down were the result of the two fields not being set; both had values of 0. Went back to the first console app and printed out the values: dwOutputId was 1535 (#define FI_JPEGFIF 1535) and dwSpecType was 2 (#define IOTYPE_ANSIPATH 2). Now if I was assigning these values outside of the class, I can see how the visibility could be different, but why is the assignment in the dll not working? Is it something about having a class in the dll?

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  • What is the ISO C++ way to directly define a conversion function to reference to array?

    - by ben
    According to the standard, a conversion function has a function-id operator conversion-type-id, which would look like, say, operator char(&)[4] I believe. But I cannot figure out where to put the function parameter list. gcc does not accept either of operator char(&())[4] or operator char(&)[4]() or anything I can think of. Now, gcc seems to accept (&operator char ())[4] but clang does not, and I am inclined to not either, since it does not seem to fit the grammar as I understand it. I do not want to use a typedef because I want to avoid polluting the namespace with it.

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  • Image/"most resembling pixel" search optimization?

    - by SigTerm
    The situation: Let's say I have an image A, say, 512x512 pixels, and image B, 5x5 or 7x7 pixels. Both images are 24bit rgb, and B have 1bit alpha mask (so each pixel is either completely transparent or completely solid). I need to find within image A a pixel which (with its' neighbors) most closely resembles image B, OR the pixel that probably most closely resembles image B. Resemblance is calculated as "distance" which is sum of "distances" between non-transparent B's pixels and A's pixels divided by number of non-transparent B's pixels. Here is a sample SDL code for explanation: struct Pixel{ unsigned char b, g, r, a; }; void fillPixel(int x, int y, SDL_Surface* dst, SDL_Surface* src, int dstMaskX, int dstMaskY){ Pixel& dstPix = *((Pixel*)((char*)(dst->pixels) + sizeof(Pixel)*x + dst->pitch*y)); int xMin = x + texWidth - searchWidth; int xMax = xMin + searchWidth*2; int yMin = y + texHeight - searchHeight; int yMax = yMin + searchHeight*2; int numFilled = 0; for (int curY = yMin; curY < yMax; curY++) for (int curX = xMin; curX < xMax; curX++){ Pixel& cur = *((Pixel*)((char*)(dst->pixels) + sizeof(Pixel)*(curX & texMaskX) + dst->pitch*(curY & texMaskY))); if (cur.a != 0) numFilled++; } if (numFilled == 0){ int srcX = rand() % src->w; int srcY = rand() % src->h; dstPix = *((Pixel*)((char*)(src->pixels) + sizeof(Pixel)*srcX + src->pitch*srcY)); dstPix.a = 0xFF; return; } int storedSrcX = rand() % src->w; int storedSrcY = rand() % src->h; float lastDifference = 3.40282347e+37F; //unsigned char mask = for (int srcY = searchHeight; srcY < (src->h - searchHeight); srcY++) for (int srcX = searchWidth; srcX < (src->w - searchWidth); srcX++){ float curDifference = 0; int numPixels = 0; for (int tmpY = -searchHeight; tmpY < searchHeight; tmpY++) for(int tmpX = -searchWidth; tmpX < searchWidth; tmpX++){ Pixel& tmpSrc = *((Pixel*)((char*)(src->pixels) + sizeof(Pixel)*(srcX+tmpX) + src->pitch*(srcY+tmpY))); Pixel& tmpDst = *((Pixel*)((char*)(dst->pixels) + sizeof(Pixel)*((x + dst->w + tmpX) & dstMaskX) + dst->pitch*((y + dst->h + tmpY) & dstMaskY))); if (tmpDst.a){ numPixels++; int dr = tmpSrc.r - tmpDst.r; int dg = tmpSrc.g - tmpDst.g; int db = tmpSrc.g - tmpDst.g; curDifference += dr*dr + dg*dg + db*db; } } if (numPixels) curDifference /= (float)numPixels; if (curDifference < lastDifference){ lastDifference = curDifference; storedSrcX = srcX; storedSrcY = srcY; } } dstPix = *((Pixel*)((char*)(src->pixels) + sizeof(Pixel)*storedSrcX + src->pitch*storedSrcY)); dstPix.a = 0xFF; } This thing is supposed to be used for texture generation. Now, the question: The easiest way to do this is brute force search (which is used in example routine). But it is slow - even using GPU acceleration and dual core cpu won't make it much faster. It looks like I can't use modified binary search because of B's mask. So, how can I find desired pixel faster? Additional Info: It is allowed to use 2 cores, GPU acceleration, CUDA, and 1.5..2 gigabytes of RAM for the task. I would prefer to avoid some kind of lengthy preprocessing phase that will take 30 minutes to finish. Ideas?

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  • how to write floating value accurately to a bin file.

    - by user319873
    Hi I am trying to dump the floating point values from my program to a bin file. Since I can't use any stdlib function, I am thinking of writting it char by char to a big char array which I am dumping in my test application to a file. It's like float a=3132.000001; I will be dumping this to a char array in 4 bytes. Code example would be:- if((a < 1.0) && (a > 1.0) || (a > -1.0 && a < 0.0)) a = a*1000000 // 6 bit fraction part. Can you please help me writting this in a better way.

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  • Type for use in template object to compare double values

    - by DaClown
    I got this n-dimensional point object: template <class T, unsigned int dimension> class Obj { protected: T coords[dimension]; static const unsigned int size = dimension; public: Obj() { }; Obj(T def) { for (unsigned int i = 0; i < size; ++i) coords[i]=def; }; Obj(const Obj& o) { for (unsigned int i = 0; i < size; ++i) coords[i] = o.coords[i]; } const Obj& operator= (const Obj& rhs) { if (this != &rhs) for (unsigned int i = 0; i < size; ++i) coords[i] = rhs.coords[i]; return *this; } virtual ~Obj() { }; T get (unsigned int id) { if (id >= size) throw std::out_of_range("out of range"); return coords[id]; } void set (unsigned int id, T t) { if (id >= size) throw std::out_of_range("out of range"); coords[id] = t; } }; and a 3D point class which uses Obj as base class: template <class U> class Point3DBase : public Obj<U,3> { typedef U type; public: U &x, &y, &z; public: Point3DBase() : x(Obj<U,3>::coords[0]), y(Obj<U,3>::coords[1]), z(Obj<U,3>::coords[2]) { }; Point3DBase(U def) : Obj<U,3>(def), x(Obj<U,3>::coords[0]), y(Obj<U,3>::coords[1]), z(Obj<U,3>::coords[2]) { }; Point3DBase(U x_, U y_, U z_) : x(Obj<U,3>::coords[0]), y(Obj<U,3>::coords[1]), z(Obj<U,3>::coords[2]) { x = x_; y = y_; z= z_; }; Point3DBase(const Point3DBase& other) : x(Obj<U,3>::coords[0]), y(Obj<U,3>::coords[1]), z(Obj<U,3>::coords[2]) { x = other.x; y = other.y; z = other.z; } // several operators ... }; The operators, basically the ones for comparison, use the simple compare-the-member-object approach like: virtual friend bool operator== (const Point3DBase<U> &lhs, const Point3DBase<U> rhs) { return (lhs.x == rhs.x && lhs.y == rhs.y && lhs.z == rhs.z); } Then it occured to me that for the comparion of double values the simply equality approach is not very useful since double values should be compared with an error margin. What would be the best approach to introduce an error margin into the point? I thought about an epsDouble type as template parameter but I can't figure out how to achieve this.

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  • Strange thing on IPv6 multicast program on Windows

    - by zhanglistar
    I have written an ipv6 multicast program on windows xp sp3. But a problem bothers me a lot. The sendto function implies no error, but I can't capture the packet using wireshark. I am sure the filter is right. Thanks in advance. And the code is as follows: #include "stdafx.h" #include <stdio.h> /* for printf() and fprintf() */ #include <winsock2.h> /* for socket(), connect(), sendto(), and recvfrom() */ #include <ws2tcpip.h> /* for ip_mreq */ #include <stdlib.h> /* for atoi() and exit() */ #include <string.h> /* for memset() */ #include <time.h> /* for timestamps */ #include <pcap.h> #include <Iphlpapi.h> #pragma comment(lib, "Ws2_32.lib") #pragma comment(lib, "wpcap.lib") #pragma comment(lib, "Iphlpapi.lib") int _tmain(int argc, _TCHAR* argv[]) { int sfd; int on, length, iResult; WSADATA wsaData; struct addrinfo Hints; struct addrinfo *multicastAddr, *localAddr; char buf[46]; // Initialize Winsock iResult = WSAStartup(MAKEWORD(2, 2), &wsaData); if (iResult != 0) { printf("WSAStartup failed: %d\n", iResult); return 1; } /* Resolve destination address for multicast datagrams */ memset(&Hints, 0, sizeof (Hints)); Hints.ai_family = AF_INET6; Hints.ai_socktype = SOCK_DGRAM; Hints.ai_protocol = IPPROTO_UDP; Hints.ai_flags = AI_NUMERICHOST; iResult = getaddrinfo("FF02::1:2", "547", &Hints, &multicastAddr); if (iResult != 0) { /* error handling */ printf("socket error: %d\n", WSAGetLastError()); return -1; } /* Get a local address with the same family (IPv4 or IPv6) as our multicast group */ Hints.ai_family = multicastAddr->ai_family; Hints.ai_socktype = SOCK_DGRAM; Hints.ai_flags = AI_PASSIVE; /* Return an address we can bind to */ if ( getaddrinfo(NULL, "546", &Hints, &localAddr) != 0 ) { printf("getaddrinfo() failed: %d\n", WSAGetLastError()); exit(-1); } // Create sending socket //sfd = socket (multicastAddr->ai_family, multicastAddr->ai_socktype, multicastAddr->ai_protocol); sfd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); if (sfd == -1) { printf("socket error: %d\n", WSAGetLastError()); return 0; } /* Bind to the multicast port */ if ( bind(sfd, localAddr->ai_addr, localAddr->ai_addrlen) != 0 ) { printf("bind() failed: %d\n", WSAGetLastError()); exit(-1); } if (multicastAddr->ai_family == AF_INET6 && multicastAddr->ai_addrlen == sizeof(struct sockaddr_in6)) /* IPv6 */ { on = 1; if (setsockopt (sfd, IPPROTO_IPV6, IPV6_MULTICAST_IF, (char *)&on, sizeof (on) /*(char *)&interface_addr, sizeof(interface_addr)*/) == -1) { printf("setsockopt error:%d\n", WSAGetLastError()); return -1; } if (setsockopt (sfd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, (char *)&on, sizeof (on) /*(char *)&interface_addr, sizeof(interface_addr)*/) == -1) { printf("setsockopt error:%d\n", WSAGetLastError()); return -1; } struct ipv6_mreq multicastRequest; /* Multicast address join structure */ /* Specify the multicast group */ memcpy(&multicastRequest.ipv6mr_multiaddr, &((struct sockaddr_in6*)(multicastAddr->ai_addr))->sin6_addr, sizeof(struct in6_addr)); /* Accept multicast from any interface */ multicastRequest.ipv6mr_interface = 0; /* Join the multicast address */ if ( setsockopt(sfd, IPPROTO_IPV6, IPV6_JOIN_GROUP, (char*) &multicastRequest, sizeof(multicastRequest)) != 0 ) { printf("setsockopt() failed: %d\n", WSAGetLastError()); return -1; } on = 1; if (setsockopt (sfd, IPPROTO_IPV6, IPV6_MULTICAST_IF, (char *)&on, sizeof (on)) == -1) { printf("setsockopt error:%d\n", WSAGetLastError()); return 0; } } memset(buf, 0, sizeof(buf)); strcpy(buf, "hello world"); iResult = sendto(sfd, buf, strlen(buf), 0, (LPSOCKADDR) multicastAddr->ai_addr, multicastAddr->ai_addrlen); if (iResult == SOCKET_ERROR) { printf("setsockopt error:%d\n", WSAGetLastError()); return -1; /* Error handling */ } return 0; }

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  • optimize output value using a class and public member

    - by wiso
    Suppose you have a function, and you call it a lot of times, every time the function return a big object. I've optimized the problem using a functor that return void, and store the returning value in a public member: #include <vector> const int N = 100; std::vector<double> fun(const std::vector<double> & v, const int n) { std::vector<double> output = v; output[n] *= output[n]; return output; } class F { public: F() : output(N) {}; std::vector<double> output; void operator()(const std::vector<double> & v, const int n) { output = v; output[n] *= n; } }; int main() { std::vector<double> start(N,10.); std::vector<double> end(N); double a; // first solution for (unsigned long int i = 0; i != 10000000; ++i) a = fun(start, 2)[3]; // second solution F f; for (unsigned long int i = 0; i != 10000000; ++i) { f(start, 2); a = f.output[3]; } } Yes, I can use inline or optimize in an other way this problem, but here I want to stress on this problem: with the functor I declare and construct the output variable output only one time, using the function I do that every time it is called. The second solution is two time faster than the first with g++ -O1 or g++ -O2. What do you think about it, is it an ugly optimization?

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  • deep or shallow copying?

    - by Dervin Thunk
    Dear all. I was wondering if there are examples of situations where you would purposefully pass an argument by value (deep copy) in C. For instance, passing a char to a function is usually cheaper in space than passing a char* (if there's no need to share the value), since char is 1 byte and pointers are, well, whatever they are in the architecture (4 in my 32 bit machine). ?(When) do you want to pass (big) deep copies to functions? if so, why?

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  • What is PHP for C# ReadBytes(stream langth)?

    - by Ole Jak
    What is PHP for C# (asuming we open some local (on server) file instead of OpenFileDialog private const int HEADER_LENGTH = 13; stream = File.OpenRead(openFileDialog.FileName); header = ReadBytes(stream, HEADER_LENGTH); And will we be able to do something like this in PHP as a next step private const byte SIGNATURE1 = 0x46; private const byte SIGNATURE2 = 0x4C; private const byte SIGNATURE3 = 0x56; if ((SIGNATURE1 != header[0]) || (SIGNATURE2 != header[1]) || (SIGNATURE3 != header[2])) throw new InvalidDataException("Not a valid FLV file!.");

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  • Transmogrify into date from multiple columns

    - by Dave Jarvis
    What is a better way to program the following SQL: str_to_date( concat(convert(D.DAY, CHAR(2)), '-', convert(M.MONTH, CHAR(2)), '-', convert(M.YEAR, CHAR(4))), '%e-%m-%Y' ) as AMOUNT_DATE I want to convert the columns D.DAY, M.MONTH, and M.YEAR to a date field using MySQL. The above works, but seems much more complicated than it needs to be. (If there's an ANSI SQL way to do it, that would be even better.) Thank you!

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