Search Results

Search found 20163 results on 807 pages for 'struct size'.

Page 478/807 | < Previous Page | 474 475 476 477 478 479 480 481 482 483 484 485  | Next Page >

• Value get changed even though I'm not using reference

  - by atch

  In code: struct Rep { const char* my_data_; Rep* my_left_; Rep* my_right_; Rep(const char*); }; typedef Rep& list; ostream& operator<<(ostream& out, const list& a_list) { int count = 0; list tmp = a_list;//----->HERE I'M CREATING A LOCAL COPY for (;tmp.my_right_;tmp = *tmp.my_right_) { out << "Object no: " << ++count << " has name: " << tmp.my_data_; //tmp = *tmp.my_right_; } return out;//------>HERE a_list is changed } I've thought that if I'll create local copy to a_list object I'll be operating on completely separate object. Why isn't so? Thanks.

  Read the article

• What is the Difference between GC.GetTotalMemory(false) and GC.GetTotalMemory(true)

  - by somaraj

  Hi, Could some one tell me the difference between GC.GetTotalMemory(false) and GC.GetTotalMemory(true); I have a small program and when i compared the results the first loop gives an put put < loop count 0 Diff = 32 for GC.GetTotalMemory(true); and < loop count 0 Diff = 0 for GC.GetTotalMemory(false); but shouldnt it be the otherway ? Smilarly rest of the loops prints some numbers ,which are different for both case. what does this number indicate .why is it changing as the loop increase. struct Address { public string Streat; } class Details { public string Name ; public Address address = new Address(); } class emp :IDisposable { public Details objb = new Details(); bool disposed = false; #region IDisposable Members public void Dispose() { Disposing(true); } void Disposing(bool disposing) { if (!disposed) disposed = disposing; objb = null; GC.SuppressFinalize(this); } #endregion } class Program { static void Main(string[] args) { long size1 = GC.GetTotalMemory(false); emp empobj = null; for (int i = 0; i < 200;i++ ) { // using (empobj = new emp()) //------- (1) { empobj = new emp(); //------- (2) empobj.objb.Name = "ssssssssssssssssss"; empobj.objb.address.Streat = "asdfasdfasdfasdf"; } long size2 = GC.GetTotalMemory(false); Console.WriteLine( "loop count " +i + " Diff = " +(size2-size1)); } } } }

  Read the article

• server/ client server connection

  - by user312054

  I have a server side program that creates a listening server side socket. The problem occurring is that it seems as if the client side sends a connect request it gets rejected if the server side socket is listening but connects if the server side program is not running. I can see the server side program getting the client request when debugging. It seems as if the client cannot connect to a listening socket. Any suggestions on a resolution? The server side accept code snippet is this. void CSocketListen::OnAccept(int nErrorCode) { CSocket::OnAccept(nErrorCode); CSocketServer* SocketPtr = new CSocketServer(); if (Accept(*SocketPtr)) { // add to list of client sockets connected } else { delete SocketPtr; } The client side code connect is like this. SOCKET cellModem; sockaddr_in handHeld; handHeld.sin_family = AF_INET; //Address family handHeld.sin_addr.s_addr = inet_addr("127.0.0.1"); handHeld.sin_port = htons((u_short)1113); //port to use cellModem=socket(AF_INET,SOCK_STREAM,0); if(cellModem == INVALID_SOCKET) { // log socket failure return false; } else { // log socket success } if (connect(cellModem,(const struct sockaddr*)&handHeld, sizeof(handHeld)) != 0 ) { // log socket connection success } else { // log socket connection failure closesocket(cellModem); }

  Read the article

• Trouble with __VA_ARGS__

  - by Noah Roberts

  C++ preprocessor __VA_ARGS__ number of arguments The accepted answer there doesn't work for me. I've tried with MSVC++ 10 and g++ 3.4.5. I also crunched the example down into something smaller and started trying to get some information printed out to me in the error: template < typename T > struct print; #include <boost/mpl/vector_c.hpp> #define RSEQ_N 10,9,8,7,6,5,4,3,2,1,0 #define ARG_N(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,N,...) N #define ARG_N_(...) ARG_N(__VA_ARGS__) #define XXX 5,RSEQ_N #include <iostream> int main() { print< boost::mpl::vector_c<int, ARG_N_( XXX ) > > g; // ARG_N doesn't work either. } It appears to me that the argument for ARG_N ends up being 'XXX' instead of 5,RSEQ_N and much less 5,10,...,0. The error output of g++ more specifically says that only one argument is supplied. Having trouble believing that the answer would be proposed and then accepted when it totally fails to work, so what am I doing wrong? Why is XXX being interpreted as the argument and not being expanded? In my own messing around everything works fine until I try to pass off VA_ARGS to a macro containing some names followed by ... like so: #define WTF(X,Y,...) X , Y , __VA_ARGS__ #define WOT(...) WTF(__VA_ARGS__) WOT(52,2,5,2,2) I've tried both with and without () in the various macros that take no input.

  Read the article

• How to std::find using a Compare object?

  - by dehmann

  I am confused about the interface of std::find. Why doesn't it take a Compare object that tells it how to compare two objects? If I could pass a Compare object I could make the following code work, where I would like to compare by value, instead of just comparing the pointer values directly: typedef std::vector<std::string*> Vec; Vec vec; std::string* s1 = new std::string("foo"); std::string* s2 = new std::string("foo"); vec.push_back(s1); Vec::const_iterator found = std::find(vec.begin(), vec.end(), s2); // not found, obviously, because I can't tell it to compare by value delete s1; delete s2; Is the following the recommended way to do it? template<class T> struct MyEqualsByVal { const T& x_; MyEqualsByVal(const T& x) : x_(x) {} bool operator()(const T& y) const { return *x_ == *y; } }; // ... vec.push_back(s1); Vec::const_iterator found = std::find_if(vec.begin(), vec.end(), MyEqualsByVal<std::string*>(s2)); // OK, will find "foo"

  Read the article

• error C2512 in precompiled header file?

  - by SoloMael

  I'm having a ridiculously strange problem. When I try to run the program below, there's an error message that says: "error C2512: 'Record' : no appropriate default constructor available". And when I double-click it, it directs me to a precompiled read-only header file named "xmemory0". Do they expect me to change a read-only file? Here's the segment of code in the file it directs me to: void construct(_Ty *_Ptr) { // default construct object at _Ptr ::new ((void *)_Ptr) _Ty(); // directs me to this line } Here's the program: #include <iostream> #include <vector> #include <string> using namespace std; const int NG = 4; // number of scores struct Record { string name; // student name int scores[NG]; double average; // Calculate the average // when the scores are known Record(int s[], double a) { double sum = 0; for(int count = 0; count != NG; count++) { scores[count] = s[count]; sum += scores[count]; } average = a; average = sum / NG; } }; int main() { // Names of the class string names[] = {"Amy Adams", "Bob Barr", "Carla Carr", "Dan Dobbs", "Elena Evans"}; // exam scores according to each student int exams[][NG]= { {98, 87, 93, 88}, {78, 86, 82, 91}, {66, 71, 85, 94}, {72, 63, 77, 69}, {91, 83, 76, 60}}; vector<Record> records(5); return 0; }

  Read the article

• updating system's time using .Net

  - by user62958

  I am trying to update my system time using the following: [StructLayout(LayoutKind.Sequential)] private struct SYSTEMTIME { public ushort wYear; public ushort wMonth; public ushort wDayOfWeek; public ushort wDay; public ushort wHour; public ushort wMinute; public ushort wSecond; public ushort wMilliseconds; } [DllImport("kernel32.dll", EntryPoint = "GetSystemTime", SetLastError = true)] private extern static void Win32GetSystemTime(ref SYSTEMTIME lpSystemTime); [DllImport("kernel32.dll", EntryPoint = "SetSystemTime", SetLastError = true)] private extern static bool Win32SetSystemTime(ref SYSTEMTIME lpSystemTime); public void SetTime() { TimeSystem correctTime = new TimeSystem(); DateTime sysTime = correctTime.GetSystemTime(); // Call the native GetSystemTime method // with the defined structure. SYSTEMTIME systime = new SYSTEMTIME(); Win32GetSystemTime(ref systime); // Set the system clock ahead one hour. systime.wYear = (ushort)sysTime.Year; systime.wMonth = (ushort)sysTime.Month; systime.wDayOfWeek = (ushort)sysTime.DayOfWeek; systime.wDay = (ushort)sysTime.Day; systime.wHour = (ushort)sysTime.Hour; systime.wMinute = (ushort)sysTime.Minute; systime.wSecond = (ushort)sysTime.Second; systime.wMilliseconds = (ushort)sysTime.Millisecond; Win32SetSystemTime(ref systime); } When I debug everything looks good and all the values are correct but when it calles the Win32SetSystemTime(ref systime) th actual time of system(display time) doesn't change and stays the same. The strange part is that when I call the Win32GetSystemTime(ref systime) it gives me the new updated time. Can someone give me some help on this?

  Read the article

• Comparing all values within a List against each other

  - by Kave

  I am a bit stuck here and can't think further. public struct CandidateDetail { public int CellX { get; set; } public int CellY { get; set; } public int CellId { get; set; } } var dic = new Dictionary<int, List<CandidateDetail>>(); How can I compare each CandidateDetail item against other CandidateDetail items within the same dictionary in the most efficient way? Example: There are three keys for the dictionary: 5, 6 and 1. Therefore we have three entries. now each of these key entries would have a List associated with. In this case let say each of these three numbers has exactly two CandidateDetails items within the list associated to each key. This means in other words we have two 5, two 6 and two 1 in different or in the same cells. I would like to know: if[5].1stItem.CellId == [6].1stItem.CellId = we got a hit. That means we have a 5 and a 6 within the same Cell if[5].2ndItem.CellId == [6].2ndItem.CellId = perfect. We found out that the other 5 and 6 are together within a different cell. if[1].1stItem.CellId == ... Now I need to check the 1 also against the other 5 and 6 to see if the one exists within the previous same two cells or not. Could a Linq expression help perhaps? I am quite stuck here... I don't know...Maybe I am taking the wrong approach. I am trying to solve the "Hidden pair" of the game Sudoku. :) http://www.sudokusolver.eu/ExplainSolveMethodD.aspx Many Thanks, Kave

  Read the article

• Is this an example for parametric polymorphism?

  - by mrt181

  Hi i am educating myself oop principles. I would like to know if this is a correct example of Cardellis definition of parametric polymorphism. Please enlighten me. The example is in cfml's script based syntax. <cfcomponent> <cfscript> public numeric function getlength(any arg, string type){ switch (arguments.type){ case "array": return arraylen(arguments.arg); break; case "struct": return structcount(arguments.arg); break; case "string": return len(arguments.arg); break; case "numeric": return len(arguments.arg); break; case "object": // gets the number of parent classes, substracting the railo base class return -1 + arraylen(structfindkey(getmetadata(arguments.arg),"extends","all")); break; default: // throw was added to railo as a user defined function to use it in cfscript throw("InvalidTypeArgument","The provided type argument is invalid for method getlength"); } } </cfscript> </cfcomponent>

  Read the article

• Is there a tool that can refactor this C code correctly?

  - by Alex

  Lets say I have the following code (the array* function are what we use for resizable arrays and they operate on pointers-to-arrays that are null initialized): typedef struct MyStruct { int i; } MyStruct; MyStruct* GetNewMyStruct(int i) { MyStruct* s = malloc(sizeof(MyStruct)); s->i = i; return s; } int SomeFunction(int number, MyStruct *elem) { MyStruct **structs = NULL; int i; for (i = 0; i < number; i++) arrayPush(&structs, GetNewMyStruct(i)); arrayPush(&structs, elem); return arraySize(&structs); } I decide that SomeFunction is too large and I want refactor it. Currently where I work we use VisualAssist X, which has some refactoring capabilities, but when I use it on this it does not work correctly. If I attempt to use it to refactor out the loop, this is what I get: void MyMethod( int number, MyStruct ** structs ) { int i; for (i = 0; i < number; i++) arrayPush(&structs, GetNewMyStruct(i)); } int SomeFunction(int number, MyStruct *elem) { MyStruct **structs = NULL; MyMethod(number, structs); arrrayPush(&structs, elem); return arraySize(&structs); } This is not correct. MyMethod should take a MyStruct ***, not a MyStruct **. This is because the code I'm refactoring takes the address of structs. The result is that the refactored version will always return 1 (since only one object has been pushed into my array) rather than number+1. Are there other tools out there that do this type of refactoring correctly?

  Read the article

• sorting names in a linked list

  - by sil3nt

  Hi there, I'm trying to sort names into alphabetical order inside a linked list but am getting a run time error. what have I done wrong here? #include <iostream> #include <string> using namespace std; struct node{ string name; node *next; }; node *A; void addnode(node *&listpointer,string newname){ node *temp; temp = new node; if (listpointer == NULL){ temp->name = newname; temp->next = listpointer; listpointer = temp; }else{ node *add; add = new node; while (true){ if(listpointer->name > newname){ add->name = newname; add->next = listpointer->next; break; } listpointer = listpointer->next; } } } int main(){ A = NULL; string name1 = "bob"; string name2 = "tod"; string name3 = "thomas"; string name4 = "kate"; string name5 = "alex"; string name6 = "jimmy"; addnode(A,name1); addnode(A,name2); addnode(A,name3); addnode(A,name4); addnode(A,name5); addnode(A,name6); while(true){ if(A == NULL){break;} cout<< "name is: " << A->name << endl; A = A->next; } return 0; }

  Read the article

• Return a list of important Python modules in a script?

  - by Jono Bacon

  Hi All, I am writing a program that categorizes a list of Python files by which modules they import. As such I need to scan the collection of .py files ad return a list of which modules they import. As an example, if one of the files I import has the following lines: import os import sys, gtk I would like it to return: ["os", "sys", "gtk"] I played with modulefinder and wrote: from modulefinder import ModuleFinder finder = ModuleFinder() finder.run_script('testscript.py') print 'Loaded modules:' for name, mod in finder.modules.iteritems(): print '%s ' % name, but this returns more than just the modules used in the script. As an example in a script which merely has: import os print os.getenv('USERNAME') The modules returned from the ModuleFinder script return: tokenize heapq __future__ copy_reg sre_compile _collections cStringIO _sre functools random cPickle __builtin__ subprocess cmd gc __main__ operator array select _heapq _threading_local abc _bisect posixpath _random os2emxpath tempfile errno pprint binascii token sre_constants re _abcoll collections ntpath threading opcode _struct _warnings math shlex fcntl genericpath stat string warnings UserDict inspect repr struct sys pwd imp getopt readline copy bdb types strop _functools keyword thread StringIO bisect pickle signal traceback difflib marshal linecache itertools dummy_thread posix doctest unittest time sre_parse os pdb dis ...whereas I just want it to return 'os', as that was the module used in the script. Can anyone help me achieve this?

  Read the article

• Communication between parent and child

  - by Pierre

  Hi every one ! I have a little problem. I have to code a simple C application that creat a process and his child (fork()) and I have to do an operation. Parent initialize the values and child calculate. I write this : #include #include #include #include #include typedef struct { int op1; char op; int op2; }Operation; Operation *varOP; void finalResult() { float result = 0; if(varOP-op == '+') result = (varOP-op1 + varOP-op2); if(varOP-op == '-') result = (varOP-op1 - varOP-op2); if(varOP-op == '*') result = (varOP-op1 * varOP-op2); if(varOP-op == '+') result = (varOP-op1 / varOP-op2); printf("%f",result); } int main () { int p; varOP = (Operation *)malloc(sizeof(Operation)); p = fork(); if(p == 0) // If child { signal(SIGUSR1, finalResult ); pause(); } if(p 0) // If parent { varOP-op = '+'; varOP-op1 = 2; varOP-op2 = 3; kill(p, SIGUSR1); wait(NULL); } return 0; } But my child is never called. Is there something wrong with my code? Thanks for your help !

  Read the article

• IOCP multiple socket completionports in same container

  - by Ohmages

  For the past couple of days I have been thinking about how to solve one of my problems I am facing, and I have tried to research the topic but don't really know what I can do. I have 2 sockets in the same struct that both have the same completionport. Problem is, they both use different protocols. Is there a way that I can find out which socket got triggered? Their called game_socket, and client_socket Example code would be something like... while (true) { error = GetQueuedCompletionStatus(CompletionPort, &BytesTransfered, (PULONG_PTR)&Key, &lpOverlapped, 0); srvc = CONTAINING_RECORD ( lpOverlapped, client , ol ); if ( error == TRUE ) { cout << endl << "SOCKET: [" << srvc->client_socket << "] TRIGGERED - WORKER THREAD" << endl; cout << endl << "BytesTransfered: [" << BytesTransfered << "]" << endl; if ( srvc->game_client triggered ) { // .. this code } else { // .. this code } Any ideas our help would be appreciated :)

  Read the article

• Is it possible to store pointers in shared memory without using offsets?

  - by Joseph Garvin

  When using shared memory, each process may mmap the shared region into a different area of their address space. This means that when storing pointers within the shared region, you need to store them as offsets of the start of the shared region. Unfortunately, this complicates use of atomic instructions (e.g. if you're trying to write a lock free algorithm). For example, say you have a bunch of reference counted nodes in shared memory, created by a single writer. The writer periodically atomically updates a pointer 'p' to point to a valid node with positive reference count. Readers want to atomically write to 'p' because it points to the beginning of a node (a struct) whose first element is a reference count. Since p always points to a valid node, incrementing the ref count is safe, and makes it safe to dereference 'p' and access other members. However, this all only works when everything is in the same address space. If the nodes and the 'p' pointer are stored in shared memory, then clients suffer a race condition: x = read p y = x + offset Increment refcount at y During step 2, p may change and x may no longer point to a valid node. The only workaround I can think of is somehow forcing all processes to agree on where to map the shared memory, so that real pointers rather than offsets can be stored in the mmap'd region. Is there any way to do that? I see MAP_FIXED in the mmap documentation, but I don't know how I could pick an address that would be safe.

  Read the article

• function objects versus function pointers

  - by kumar_m_kiran

  Hi All, I have two questions related to function objects and function pointers, Question : 1 When I read the different uses sort algorithm of STL, I see that the third parameter can be a function objects, below is an example class State { public: //... int population() const; float aveTempF() const; //... }; struct PopLess : public std::binary_function<State,State,bool> { bool operator ()( const State &a, const State &b ) const { return popLess( a, b ); } }; sort( union, union+50, PopLess() ); Question : Now, How does the statement, sort(union, union+50,PopLess()) work? PopLess() must be resolved into something like PopLess tempObject.operator() which would be same as executing the operator () function on a temporary object. I see this as, passing the return value of overloaded operation i.e bool (as in my example) to sort algorithm. So then, How does sort function resolve the third parameter in this case? Question : 2 Question Do we derive any particular advantage of using function objects versus function pointer? If we use below function pointer will it derive any disavantage? inline bool popLess( const State &a, const State &b ) { return a.population() < b.population(); } std::sort( union, union+50, popLess ); // sort by population PS : Both the above references(including example) are from book "C++ Common Knowledge: Essential Intermediate Programming" by "Stephen C. Dewhurst". I was unable to decode the topic content, thus have posted for help. Thanks in advance for your help.

  Read the article

• Hadoop/MapReduce: Reading and writing classes generated from DDL

  - by Dave

  Hi, Can someone walk me though the basic work-flow of reading and writing data with classes generated from DDL? I have defined some struct-like records using DDL. For example: class Customer { ustring FirstName; ustring LastName; ustring CardNo; long LastPurchase; } I've compiled this to get a Customer class and included it into my project. I can easily see how to use this as input and output for mappers and reducers (the generated class implements Writable), but not how to read and write it to file. The JavaDoc for the org.apache.hadoop.record package talks about serializing these records in Binary, CSV or XML format. How do I actually do that? Say my reducer produces IntWritable keys and Customer values. What OutputFormat do I use to write the result in CSV format? What InputFormat would I use to read the resulting files in later, if I wanted to perform analysis over them?

  Read the article

• Experts help needed on libcurl programming in sending HTTP HEAD Request.

  - by Mani

  Hi all, I need clarifications on using libcurl for the following: I need to send an http HEAD request shown as below :: HEAD /mshare/3/30002:12:primary/stream_xNKNVH.mpeg HTTP/1.1 Host: 192.168.70.1:8080 Accept: */* User-Agent: Kreatel_IP-STB getcontentFeatures.dlna.org: 1 The code I wrote (shown below) , sends the HEAD Request in slightly different way: curl_global_init(CURL_GLOBAL_ALL); CURL* ctx = NULL; const char *url = "http://192.168.70.1:8080/mshare/3/30002:12:primary/stream_xNKNVH.mpeg" ; char *returnString; struct curl_slist *headers = NULL; ctx = curl_easy_init(); headers = curl_slist_append(headers,"Accept: /"); headers = curl_slist_append(headers,"User-Agent: Kreatel_IP-STB");\ headers = curl_slist_append(headers,"getcontentFeatures.dlna.org: 1"); headers = curl_slist_append(headers,"Pragma:"); headers = curl_slist_append(headers,"Proxy-Connection:"); curl_easy_setopt(ctx,CURLOPT_HTTPHEADER , headers ); curl_easy_setopt(ctx,CURLOPT_NOBODY ,1 ); curl_easy_setopt(ctx,CURLOPT_VERBOSE, 1); curl_easy_setopt(ctx,CURLOPT_URL,url ); curl_easy_setopt(ctx,CURLOPT_NOPROGRESS ,1 ); curl_easy_perform(ctx); curl_easy_cleanup(ctx); curl_global_cleanup(); The code shown above sends the HEAD Request in slightly different form (shown below) HEAD http://192.168.70.1:8080/mshare/3/30002:12:primary/stream_xNKNVH.mpeg HTTP/1.1 Host: 192.168.70.1:8080 Proxy-Connection: Keep-Alive Accept: */* User-Agent: Kreatel_IP-STB getcontentFeatures.dlna.org: 1 Can any one , share the appropriate code ?

  Read the article

• Removing specific XML tags

  - by iTayb

  I'd like to make an application that removes duplicates from my wpl (Windows PlayList) files. The wpl struct is something like this: <?wpl version="1.0"?> <smil> <head> <meta name="Generator" content="Microsoft Windows Media Player -- 11.0.5721.5145"/> <meta name="AverageRating" content="55"/> <meta name="TotalDuration" content="229844"/> <meta name="ItemCount" content="978"/> <author/> <title>english</title> </head> <body> <seq> <media src="D:\Anime con 2006\Shits\30 Seconds to Mars - 30 Seconds to Mars\30 Seconds to Mars - Capricorn.mp3" tid="{BCC6E6B9-D0F3-449C-91A9-C6EEBD92FFAE}" cid="{D38701EF-1764-4331-A332-50B5CA690104}"/> <media src="E:\emule.incoming\Ke$ha - Coming Unglued.mp3" tid="{E2DB18E5-0449-4FE3-BA09-9DDE18B523B1}"/> <media src="E:\emule.incoming\Lady Gaga - Bad Romance.mp3" tid="{274BD12B-5E79-4165-9314-00DB045D4CD8}"/> <media src="E:\emule.incoming\David Guetta -Sexy Bitch Feat. Akon.mp3" tid="{46DA1363-3DFB-4030-A7A9-88E13DF30677}"/> </seq> </body> </smil> This looks like standard XML file. How can I load the file and get the src value of each media tag? How can I remove specific media, in case of duplicates? Thank you very much.

  Read the article

• recommended format to save time with MJD + BCD format in database

  - by pierr

  Hi, There is a time represented in MJD and BCD format with 5 bytes .I am wondering what is the recommended format to save this date-time in the sqlite database so that user can search against it ? My first attempt is to save it just as it is, that is a 5 bytes string. The user will use the same format to search and the result will be converted to unix time by the user with following code. However, later, I was suggested to save the time in the integer - the UTC time, for example. But I can not find a standard way to do the conversion. I feel this is a common issue and would like to hear your comments. time_t sidate_to_unixtime(unsigned char sidate[]) { int k = 0; struct tm tm; double mjd; /* check for the undefined value */ if ((sidate[0] == 0xff) && (sidate[1] == 0xff) && (sidate[2] == 0xff) && (sidate[3] == 0xff) && (sidate[4] == 0xff)) { return -1; } memset(&tm, 0, sizeof(tm)); mjd = (sidate[0] << 8) | sidate[1]; tm.tm_year = (int) ((mjd - 15078.2) / 365.25); tm.tm_mon = (int) (((mjd - 14956.1) - (int) (tm.tm_year * 365.25)) / 30.6001); tm.tm_mday = (int) mjd - 14956 - (int) (tm.tm_year * 365.25) - (int) (tm.tm_mon * 30.6001); if ((tm.tm_mon == 14) || (tm.tm_mon == 15)) k = 1; tm.tm_year += k; tm.tm_mon = tm.tm_mon - 2 - k * 12; tm.tm_sec = bcd_to_integer(sidate[4]); tm.tm_min = bcd_to_integer(sidate[3]); tm.tm_hour = bcd_to_integer(sidate[2]); return mktime(&tm); }

  Read the article

• In C++, what is the scope resolution ("order of precedence") for shadowed variable names?

  - by Emile Cormier

  In C++, what is the scope resolution ("order of precedence") for shadowed variable names? I can't seem to find a concise answer online. For example: #include <iostream> int shadowed = 1; struct Foo { Foo() : shadowed(2) {} void bar(int shadowed = 3) { std::cout << shadowed << std::endl; // What does this output? { int shadowed = 4; std::cout << shadowed << std::endl; // What does this output? } } int shadowed; }; int main() { Foo().bar(); } I can't think of any other scopes where a variable might conflict. Please let me know if I missed one. What is the order of priority for all four shadow variables when inside the bar member function?

  Read the article

• Elegant way of parsing Data files for Simulation

  - by sc_ray

  I am working on this project where I need to read in a lot of data from .dat files and use the data to perform simulations. The data in my .dat file looks as follows: DeviceID InteractingDeviceID InteractionStartTime InteractionEndTime 1 2 1101 1105 1,2 1101 and 1105 are tab delimited and it means Device 1 interacted with Device 2 at 1101 ms and ended the interaction at 1105ms. I have a trace data sets that compile thousands of such interactions and my job is to analyze these interactions. The first step is to parse the file. The language of choice is C++. The approach I was thinking of taking was to read the file, for every line that's read create a Device Object. This Device object will contain the property DeviceId and an array/vector of structs, that will contain a list of all the devices the given DeviceId interacted with over the course of the simulation.The struct will contain the Interacting Device Id, Interaction Start Time and Interaction End Time. I have a two fold question here: Is my approach correct? If I am on the right track, how do I rapidly parse these tab delimited data files and create Device objects without excessive memory overhead using C++? A push in the right direction will be much appreciated. Thanks

  Read the article

• Qt and variadic functions

  - by Noah Roberts

  OK, before lecturing me on the use of C-style variadic functions in C++...everything else has turned out to require nothing short of rewriting the Qt MOC. What I'd like to know is whether or not you can have a "slot" in a Qt object that takes an arbitrary amount/type of arguments. The thing is that I really want to be able to generate Qt objects that have slots of an arbitrary signature. Since the MOC is incompatible with standard preprocessing and with templates, it's not possible to do so with either direct approach. I just came up with another idea: struct funky_base : QObject { Q_OBJECT funky_base(QObject * o = 0); public slots: virtual void the_slot(...) = 0; }; If this is possible then, because you can make a template that is a subclass of a QObject derived object so long as you don't declare new Qt stuff in it, I should be able to implement a derived templated type that takes the ... stuff and turns it into the appropriate, expected types. If it is, how would I connect to it? Would this work? connect(x, SIGNAL(someSignal(int)), y, SLOT(the_slot(...))); If nobody's tried anything this insane and doesn't know off hand, yes I'll eventually try it myself...but I am hoping someone already has existing knowledge I can tap before possibly wasting my time on it.

  Read the article

• Volatile fields in C#

  - by Danny Chen

  From the specification 10.5.3 Volatile fields: The type of a volatile field must be one of the following: A reference-type. The type byte, sbyte, short, ushort, int, uint, char, float, bool, System.IntPtr, or System.UIntPtr. An enum-type having an enum base type of byte, sbyte, short, ushort, int, or uint. First I want to confirm my understanding is correct: I guess the above types can be volatile because they are stored as a 4-bytes unit in memory(for reference types because of its address), which guarantees the read/write operation is atomic. A double/long/etc type can't be volatile because they are not atomic reading/writing since they are more than 4 bytes in memory. Is my understanding correct? And the second, if the first guess is correct, why a user defined struct with only one int field in it(or something similar, 4 bytes is ok) can't be volatile? Theoretically it's atomic right? Or it's not allowed simply because that all user defined structs(which is possibly more than 4 bytes) are not allowed to volatile by design?

  Read the article

• Unboxing to unknown type

  - by Robert

  I'm trying to figure out syntax that supports unboxing an integral type (short/int/long) to its intrinsic type, when the type itself is unknown. Here is a completely contrived example that demonstrates the concept: // Just a simple container that returns values as objects struct DataStruct { public short ShortVale; public int IntValue; public long LongValue; public object GetBoxedShortValue() { return LongValue; } public object GetBoxedIntValue() { return LongValue; } public object GetBoxedLongValue() { return LongValue; } } static void Main( string[] args ) { DataStruct data; // Initialize data - any value will do data.LongValue = data.IntValue = data.ShortVale = 42; DataStruct newData; // This works if you know the type you are expecting! newData.ShortVale = (short)data.GetBoxedShortValue(); newData.IntValue = (int)data.GetBoxedIntValue(); newData.LongValue = (long)data.GetBoxedLongValue(); // But what about when you don't know? newData.ShortVale = data.GetBoxedShortValue(); // error newData.IntValue = data.GetBoxedIntValue(); // error newData.LongValue = data.GetBoxedLongValue(); // error } In each case, the integral types are consistent, so there should be some form of syntax that says "the object contains a simple type of X, return that as X (even though I don't know what X is)". Because the objects ultimately come from the same source, there really can't be a mismatch (short != long). I apologize for the contrived example, it seemed like the best way to demonstrate the syntax. Thanks.

  Read the article

< Previous Page | 474 475 476 477 478 479 480 481 482 483 484 485  | Next Page >