Search Results

Search found 1221 results on 49 pages for 'argv'.

Page 38/49 | < Previous Page | 34 35 36 37 38 39 40 41 42 43 44 45  | Next Page >

• UIDocumentInteractionController & ARC: [UIPopoverController dealloc] reached while popover is still visible

  - by muffel

  This issue or similar issues have been discussed here before, but I didn't find any working solution for me. I am using the following code to display a UIDocumentInteractionController on an ARC-enabled iOS 7 project: - (void) exportDoc{ // [...] docController = [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:path]]; docController.delegate = self; [docController presentOpenInMenuFromBarButtonItem:mainMenuButton animated:YES]; } First I didn't want to create a property that holds the controller reference, but as many people said that there are not alternatives to it. It is defined as @property (strong) UIDocumentInteractionController* docController; exportDoc is run in the main thread using NSOperationQueue. Whenever it is executed, I get the following error message: Terminating app due to uncaught exception 'NSGenericException', reason: '-[UIPopoverController dealloc] reached while popover is still visible.' This is what the backtrace says: (lldb) bt * thread #1: tid = 0x1c97d9, 0x000000019a23c1c0 libobjc.A.dylibobjc_exception_throw, queue = 'com.apple.main-thread', stop reason = breakpoint 2.1 frame #0: 0x000000019a23c1c0 libobjc.A.dylibobjc_exception_throw frame #1: 0x000000018d982e90 CoreFoundation+[NSException raise:format:] + 128 frame #2: 0x0000000190bc348c UIKit-[UIPopoverController dealloc] + 96 frame #3: 0x0000000190e18fc8 UIKit-[UIDocumentInteractionController dealloc] + 168 frame #4: 0x000000019a255474 libobjc.A.dylib(anonymous namespace)::AutoreleasePoolPage::pop(void*) + 524 frame #5: 0x000000018d881988 CoreFoundation_CFAutoreleasePoolPop + 28 frame #6: 0x000000018e42cb18 Foundation-[NSOperationInternal _start:] + 892 frame #7: 0x000000018e4eea38 Foundation__NSOQSchedule_f + 76 frame #8: 0x000000019a813fd4 libdispatch.dylib_dispatch_client_callout + 16 frame #9: 0x000000019a8171dc libdispatch.dylib_dispatch_main_queue_callback_4CF + 336 frame #10: 0x000000018d942c2c CoreFoundation__CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE + 12 frame #11: 0x000000018d940f6c CoreFoundation__CFRunLoopRun + 1452 frame #12: 0x000000018d881c20 CoreFoundationCFRunLoopRunSpecific + 452 frame #13: 0x0000000193511c0c GraphicsServicesGSEventRunModal + 168 frame #14: 0x00000001909b2fdc UIKitUIApplicationMain + 1156 * frame #15: 0x000000010000947c MyApplicationmain(argc=1, argv=0x000000016fdfbc80) + 108 at main.m:16 frame #16: 0x000000019a82faa0 libdyld.dylibstart + 4 As far as I understand the autoreleasepool just releases the controller. Shouldn't this be prevented by using a strong property just as I did? Do you have any idea what the problem can be and how I can solve it?

  Read the article

• Boost threading/mutexs, why does this work?

  - by Flamewires

  Code: #include <iostream> #include "stdafx.h" #include <boost/thread.hpp> #include <boost/thread/mutex.hpp> using namespace std; boost::mutex mut; double results[10]; void doubler(int x) { //boost::mutex::scoped_lock lck(mut); results[x] = x*2; } int _tmain(int argc, _TCHAR* argv[]) { boost::thread_group thds; for (int x = 10; x>0; x--) { boost::thread *Thread = new boost::thread(&doubler, x); thds.add_thread(Thread); } thds.join_all(); for (int x = 0; x<10; x++) { cout << results[x] << endl; } return 0; } Output: 0 2 4 6 8 10 12 14 16 18 Press any key to continue . . . So...my question is why does this work(as far as i can tell, i ran it about 20 times), producing the above output, even with the locking commented out? I thought the general idea was: in each thread: calculate 2*x copy results to CPU register(s) store calculation in correct part of array copy results back to main(shared) memory I would think that under all but perfect conditions this would result in some part of the results array having 0 values. Is it only copying the required double of the array to a cpu register? Or is it just too short of a calculation to get preempted before it writes the result back to ram? Thanks.

  Read the article

• C: Fifo between threads, writing and reading strings

  - by Yonatan

  Hello once more dear internet, I writing a small program that among other things, writes a log file of commands received. to do that, I want to use a thread that all it should do is just attempt to read from a pipe, while the main thread will write into that pipe whenever it should. Since i don't know the length of each string command, i thought about writing and reading the pointer to the char buf[MAX_MESSAGE_LEN]. Since what i've tried so far doesn't work, i'll post my best effort :P char str[] = "hello log thread 123456789 10 11 12 13 14 15 16 17 18 19\n"; if (pipe(pipe_fd) != 0) return -1; pthread_t log_thread; pthread_create(&log_thread,NULL, log_thread_start, argv[2]); success_write = 0; do { write(pipe_fd[1],(void*)&str,sizeof(char*)); } while (success_write < sizeof(char*)); and the thread does this: char buffer[MAX_MSGLEN]; int success_read; success_read = 0; //while(1) { do { success_read += read(pipe_fd[0],(void*)&buffer, sizeof(char*)); } while (success_read < sizeof(char*)); //} printf("%s",buffer); (Sorry if this doesn't indent, i can't seem to figure out this editor...) oh, and pipe_fd[2] is a global parameter. So, any help with this, either by the way i thought of, or another way i could read strings without knowing the length, would be much appreciated. On a side note, i'm working on Eclipse IDE C/C++, version 1.2.1 and i can't seem to set up the compiler so it will link the pthread library to my project. I've resorted to writing my own Makefile to make it (pun intended :P) work. Anyone knows what to do ? i've looked online, but all i find are solutions that are probably good on an older version because the tabs and option keys are different. Anyways, Thanks a bunch internet ! Yonatan

  Read the article

• Concise description of how .h and .m files interact in objective c?

  - by RJ86

  I have just started learning objective C and am really confused how the .h and .m files interact with each other. This simple program has 3 files: Fraction.h #import <Foundation/NSObject.h> @interface Fraction : NSObject { int numerator; int denominator; } - (void) print; - (void) setNumerator: (int) n; - (void) setDenominator: (int) d; - (int) numerator; - (int) denominator; @end Fraction.m #import "Fraction.h" #import <stdio.h> @implementation Fraction -(void) print { printf( "%i/%i", numerator, denominator ); } -(void) setNumerator: (int) n { numerator = n; } -(void) setDenominator: (int) d { denominator = d; } -(int) denominator { return denominator; } -(int) numerator { return numerator; } @end Main.m #import <stdio.h> #import "Fraction.h" int main(int argc, char *argv[]) { Fraction *frac = [[Fraction alloc] init]; [frac setNumerator: 1]; [frac setDenominator: 3]; printf( "The fraction is: " ); [frac print]; printf( "\n" ); [frac release]; return 0; } From what I understand, the program initially starts running the main.m file. I understand the basic C concepts but this whole "class" and "instance" stuff is really confusing. In the Fraction.h file the @interface is defining numerator and denominator as an integer, but what else is it doing below with the (void)? and what is the purpose of re-defining below? I am also quite confused as to what is happening with the (void) and (int) portions of the Fraction.m and how all of this is brought together in the main.m file. I guess what I am trying to say is that this seems like a fairly easy program to learn how the different portions work with each other - could anyone explain in non-tech jargon?

  Read the article

• CURL C API: callback was not called

  - by Pierre

  Hi all, The code below is a test for the CURL C API . The problem is that the callback function write_callback is never called. Why ? /** compilation: g++ source.cpp -lcurl */ #include <assert.h> #include <iostream> #include <cstdlib> #include <cstring> #include <cassert> #include <curl/curl.h> using namespace std; static size_t write_callback(void *ptr, size_t size, size_t nmemb, void *userp) { std::cerr << "CALLBACK WAS CALLED" << endl; exit(-1); return size*nmemb; } static void test_curl() { int any_data=1; CURLM* multi_handle=NULL; CURL* handle_curl = ::curl_easy_init(); assert(handle_curl!=NULL); ::curl_easy_setopt(handle_curl, CURLOPT_URL, "http://en.wikipedia.org/wiki/Main_Page"); ::curl_easy_setopt(handle_curl, CURLOPT_WRITEDATA, &any_data); ::curl_easy_setopt(handle_curl, CURLOPT_VERBOSE, 1); ::curl_easy_setopt(handle_curl, CURLOPT_WRITEFUNCTION, write_callback); ::curl_easy_setopt(handle_curl, CURLOPT_USERAGENT, "libcurl-agent/1.0"); multi_handle = ::curl_multi_init(); assert(multi_handle!=NULL); ::curl_multi_add_handle(multi_handle, handle_curl); int still_running=0; /* lets start the fetch */ while(::curl_multi_perform(multi_handle, &still_running) == CURLM_CALL_MULTI_PERFORM ); std::cerr << "End of curl_multi_perform."<< endl; //cleanup should go here ::exit(EXIT_SUCCESS); } int main(int argc,char** argv) { test_curl(); return 0; } Many thanks Pierre

  Read the article

• Template Child Class Overriding a Parent Class's Virtual Function

  - by user334066

  The below code compiles with gcc v4.3.3 and the templated child class seems to be overriding a virtual function in the parent, but doesn't that break the rule that you cannot have a virtual template function? Or is something else happening that I don't understand? class BaseClass { public: virtual void Func(int var) { std::cout<<"Base int "<<var<<std::endl; } virtual void Func(double var) { std::cout<<"Base double "<<var<<std::endl; } }; template <class TT> class TemplateClass : public BaseClass { public: using BaseClass::Func; virtual void Func(TT var) { std::cout<<"Child TT "<<var<<std::endl; } }; int main(int argc, char **argv) { BaseClass a; TemplateClass<int> b; BaseClass *c = new TemplateClass<int>; int intVar = 3; double doubleVar = 5.5; a.Func(intVar); a.Func(doubleVar); b.Func(intVar); b.Func(doubleVar); c->Func(intVar); c->Func(doubleVar); delete c; } This then outputs: Base int 3 Base double 5.5 Child TT 3 Base double 5.5 Child TT 3 Base double 5.5 as I hoped, but I'm not sure why it works.

  Read the article

• Console in VS 2012 Express for C++?

  - by Live2Code

  I'm very new to programming, so be nice. I was using Eclipse for C/C++ devs for a while, but it seemed quite buggy so I was advised to switch to Visual Studio Express. I'm just testing out with a simple "Hello World" program #include <iostream> #include <string> using namespace std; int main( int argc, char ** argv ) { string response; cout << "Gimme a string: " << flush; cin >> response; cout << "The string is: " << response << endl; system("pause"); return 0; } not much to go wrong there anyway, I noticed that there is no "console" like in Eclipse. All of the text pops up in a little command prompt window. And, also, this window closes right after displaying new text if there is no other things to do after it (like a cin). I have been told that I can use system("pause") but there has to be a better way. In Eclipse, the text would not suddenly disappear because the console window closed. i know this question might be a little confusing, comment and I'll try to explain what I'm saying. Or paste the codes into your Visual Studio 2012 Express Edition. But is there a way to display all of my text and whatever in a "console" as opposed to a command prompt-type window; and why does it always close before I can read the last thing?

  Read the article

• In Perl, how can I wait for threads to end in parallel?

  - by Pmarcoen

  I have a Perl script that launches 2 threads,one for each processor. I need it to wait for a thread to end, if one thread ends a new one is spawned. It seems that the join method blocks the rest of the program, therefore the second thread can't end until everything the first thread does is done which sort of defeats its purpose. I tried the is_joinable method but that doesn't seem to do it either. Here is some of my code : use threads; use threads::shared; @file_list = @ARGV; #Our file list $nofiles = $#file_list + 1; #Real number of files $currfile = 1; #Current number of file to process my %MSG : shared; #shared hash $thr0 = threads->new(\&process, shift(@file_list)); $currfile++; $thr1 = threads->new(\&process, shift(@file_list)); $currfile++; while(1){ if ($thr0->is_joinable()) { $thr0->join; #check if there are files left to process if($currfile <= $nofiles){ $thr0 = threads->new(\&process, shift(@file_list)); $currfile++; } } if ($thr1->is_joinable()) { $thr1->join; #check if there are files left to process if($currfile <= $nofiles){ $thr1 = threads->new(\&process, shift(@file_list)); $currfile++; } } } sub process{ print "Opening $currfile of $nofiles\n"; #do some stuff if(some condition){ lock(%MSG); #write stuff to hash } print "Closing $currfile of $nofiles\n"; } The output of this is : Opening 1 of 4 Opening 2 of 4 Closing 1 of 4 Opening 3 of 4 Closing 3 of 4 Opening 4 of 4 Closing 2 of 4 Closing 4 of 4

  Read the article

• Boost program will not working on Linux

  - by Martin Lauridsen

  Hi SOF, I have this program which uses Boost::Asio for sockets. I pretty much altered some code from the Boost examples. The program compiles and runs just like it should on Windows in VS. However, when I compile the program on Linux and run it, I get a Segmentation fault. I posted the code here The command I use to compile it is this: c++ -I/appl/htopopt/Linux_x86_64/NTL-5.4.2/include -I/appl/htopopt/Linux_x86_64/boost_1_43_0/include mpqs.cpp mpqs_polynomial.cpp mpqs_host.cpp -o mpqs_host -L/appl/htopopt/Linux_x86_64/NTL-5.4.2/lib -lntl -L/appl/htopopt/Linux_x86_64/gmp-4.2.1/lib -lgmp -lm -L/appl/htopopt/Linux_x86_64/boost_1_43_0/lib -lboost_system -lboost_thread -static -lpthread By commenting out code, I have found out that I get the Segmentation fault due to the following line: boost::asio::io_service io_service; Can anyone provide any assistance, as to what may be the problem (and the solution)? Thanks! Edit: I tried changing the program to a minimal example, using no other libraries or headers, just boost/asio.hpp: #define DEBUG 0 #include <boost/asio.hpp> int main(int argc, char* argv[]) { boost::asio::io_service io_service; return 0; } I also removed other library inclusions and linking on compilation, however this minimal example still gives me a segmentation fault.

  Read the article

• Django tutorial says I haven't set DATABASE_ENGINE setting yet... but I have

  - by Joe

  I'm working through the Django tutorial and receiving the following error when I run the initial python manage.py syncdb: Traceback (most recent call last): File "manage.py", line 11, in <module> execute_manager(settings) File "/Library/Python/2.6/site-packages/django/core/management/__init__.py", line 362 in execute_manager utility.execute() File "/Library/Python/2.6/site-packages/django/core/management/__init__.py", line 303, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "/Library/Python/2.6/site-packages/django/core/management/base.py", line 195, in run_from_argv self.execute(*args, **options.__dict__) File "/Library/Python/2.6/site-packages/django/core/management/base.py", line 222, in execute output = self.handle(*args, **options) File "/Library/Python/2.6/site-packages/django/core/management/base.py", line 351, in handle return self.handle_noargs(**options) File "/Library/Python/2.6/site-packages/django/core/management/commands/syncdb.py", line 49, in handle_noargs cursor = connection.cursor() File "/Library/Python/2.6/site-packages/django/db/backends/dummy/base.py", line 15, in complain raise ImproperlyConfigured, "You haven't set the DATABASE_ENGINE setting yet." django.core.exceptions.ImproperlyConfigured: You haven't set the DATABASE_ENGINE setting yet. My settings.py looks like: DATABASES = { 'default': { 'ENGINE': 'django.db.backends.mysql', # Add 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'. 'NAME': 'dj_tut', # Or path to database file if using sqlite3. 'USER': '', # Not used with sqlite3. 'PASSWORD': '', # Not used with sqlite3. 'HOST': '', # Set to empty string for localhost. Not used with sqlite3. 'PORT': '', # Set to empty string for default. Not used with sqlite3. } } I'm guessing this is something simple, but why isn't it seeing the ENGINE setting?

  Read the article

• PHP Magic faster than simply setting the class attribute?

  - by Marc Trudel

  Well, not exactly that, but here is an example. Can anyone explain the difference between B and C? How can it be faster to use a magic function to dynamically set a value instead of simply setting the value in the attribute definition? Here is some code: [root@vm-202-167-238-17 ~]# cat test.php; for d in A B C; do echo "------"; ./test.php $d; done; #!/usr/bin/php <?php $className = $argv[1]; class A { public function __get($a) { return 5; } } class B { public $a = 5; } class C { public function __get($a) { $this->a = 5; return 5; } } $a = new $className; $start = microtime(true); for ($i=0; $i < 1000000; $i++) $b = $a->a; $end = microtime(true); echo (($end - $start) * 1000) ." msec\n"; ------ 598.90794754028 msec ------ 205.48391342163 msec ------ 189.7759437561 msec

  Read the article

• Why does this code leak? (simple codesnippet)

  - by Ela782

  Visual Studio shows me several leaks (a few hundred lines), in total more than a few MB. I traced it down to the following "helloWorld example". The leak disappears if I comment out the H5::DataSet.getSpace() line. #include "stdafx.h" #include <iostream> #include "cpp/H5Cpp.h" int main(int argc, char *argv[]) { _CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF ); // dump leaks at return H5::H5File myfile; try { myfile = H5::H5File("C:\\Users\\yyy\\myfile.h5", H5F_ACC_RDONLY); } catch (H5::Exception& e) { std::string msg( std::string( "Could not open HDF5 file.\n" ) + e.getCDetailMsg() ); throw msg; } H5::Group myGroup = myfile.openGroup("/so/me/group"); H5::DataSet myDS = myGroup.openDataSet("./myfloatvec"); hsize_t dims[1]; //myDS.getSpace().getSimpleExtentDims(dims, NULL); // <-- here's the leak H5::DataSpace dsp = myDS.getSpace(); // The H5::DataSpace seems to leak dsp.getSimpleExtentDims(dims, NULL); //dsp.close(); // <-- doesn't help either std::cout << "Dims: " << dims[0] << std::endl; // <-- Works as expected return 0; } Any help would be appreciated. I've been on this for hours, I hate unclean code...

  Read the article

• complete nub.. iostream file not found

  - by user1742389

  folks I am almost completely new to programming so please bear with me. I am using the first example from lydia.com c++ videos and failing. I am using Xcode 4.5.1 with a c++ command line project instead of eclipse and I am getting an error on compile of iostream file not found. the code is simple and I will include exactly what I have at the end of this message. I thought that iostream was a standard header that came with all even remotely recent versions of c++ compilers and am shocked to get this error and I cannot find any way to fix this. please tell me whats going on. #include <iostream> #include <stdio.h> #include <sstream> #include <vector> int main(int argc, char ** argv) { stringstream version; version << "GCC Version"; _GNUC_<<"."<<_GNUC_MINOR_<<"."<<_GNUC_PATCHLEVEL_<<_"\nVersion String: " <<_VERSION_; cout <<version.string() endl; vector<string> v={"one","two","three"}; for ( s : v ) { cout << s <<endl; } // insert code here... printf("Hello, World!\n"); return 0; } Thanks.

  Read the article

• Objective-C ref count and autorelease

  - by turbovince

  Hey guys, suppose the following code: int main (int argc, const char * argv[]) { //[...] Rectangle* myRect = [[Rectangle alloc] init]; Vector2* newOrigin = [[[Vector2 alloc] init] autorelease]; // ref count 1 [newOrigin setX: 50.0f]; [myRect setOrigin: newOrigin]; // ref count 2 [myRect.origin setXY: 25.0f :100.0f]; // ref count goes to 3... why ? [myRect release]; [pool drain]; return 0; } Rectangle's origin is declared as a (retain) synthesized property. Just wondering 2 things: Why does ref count goes to 3 when using the getter accessor of Rectangle's origin? Am I doing something wrong ? With a ref count of 3, I don't understand how this snippet of code cannot leak. Calling release on myRect will make it go down to 2 since I call release on the origin in dealloc(). But then, when does autorelease take effect? Thanks!

  Read the article

• How to wrap Ruby strings in HTML tags

  - by Jason H.

  Hi all: I'm looking for help on two things. 1) I'm looking for a way for Ruby to wrap strings in HTML. I have a program I'm writing that generates a Hash of word frequencies for a text file and I want to take the results and place it into an HTML file rather than print to STDOUT. I'm thinking each string needs to be wrapped in an HTML paragraph tag using readlines() or something, but I can't quite figure it out. Then, once I've wrapped the strings in HTML 2) I want to write to an empty HTML file. Right now my program looks like: filename = File.new(ARGV[0]).read().downcase().scan(/[\w']+/) frequency = Hash.new(0) words.each { |word| frequency[word] +=1 } frequency.sort_by { |x,y| y }.reverse().each{ |w,f| puts "#{f}, #{w}" } So if we ran a text file through this and received: 35, the 27, of 20, to 16, in # . . . I'd want to export to an HTML file that wraps the lines like: <p>35, the</p> <p>27, of</p> <p>20, to</p> <p>16, in</p> # . . . Thanks for any tips in advance!

  Read the article

• Gradual memory leak and slowdown in loop

  - by Benji XVI

  I have a simple foundation tool that exports every frame of a movie as a .tiff file. Here is the relevant code: NSString* movieLoc = [NSString stringWithCString:argv[1]]; QTMovie *sourceMovie = [QTMovie movieWithFile:movieLoc error:nil]; int i=0; while (QTTimeCompare([sourceMovie currentTime], [sourceMovie duration]) != NSOrderedSame) { // save image of movie to disk NSAutoreleasePool *arp = [[NSAutoreleasePool alloc] init]; NSString *filePath = [NSString stringWithFormat:@"/somelocation_%d.tiff", i++]; NSData *currentImageData = [[sourceMovie currentFrameImage] TIFFRepresentation]; [currentImageData writeToFile:filePath atomically:NO]; NSLog(@"%@", filePath); [sourceMovie stepForward]; [arp release]; } [pool drain]; return 0; As you can see, in order to prevent very large memory buildups with the various transparently-autoreleased variables in the loop, we create, and flush, an autoreleasepool with every run through the loop. However, over the course of stepping through a movie, the amount of memory used by the program still gradually increases, and the speed at which frames are processed drops precipitously. (From ~0.5 seconds per frame at the start, to ~2 seconds per frame by the 250th frame.) The only thing I can think can be causing the gradual memory leak is a buildup of the NSAutoreleasePool objects themselves. Am I right in thinking they will only be deallocated when the outer pool is released? If so, is there a better memory management solution here? Creating a pool every run through the loop seems a little hacky. And if not, what is causing the slow memory leak? (It is not NSStrings, and much too slow to be NSImages or NSDatas.) And what could be causing the slowdown?

  Read the article

• GetIpAddrTable() leaks memory. How to resolve that?

  - by Stabledog

  On my Windows 7 box, this simple program causes the memory use of the application to creep up continuously, with no upper bound. I've stripped out everything non-essential, and it seems clear that the culprit is the Microsoft Iphlpapi function "GetIpAddrTable()". On each call, it leaks some memory. In a loop (e.g. checking for changes to the network interface list), it is unsustainable. There seems to be no async notification API which could do this job, so now I'm faced with possibly having to isolate this logic into a separate process and recycle the process periodically -- an ugly solution. Any ideas? // IphlpLeak.cpp - demonstrates that GetIpAddrTable leaks memory internally: run this and watch // the memory use of the app climb up continuously with no upper bound. #include <stdio.h> #include <windows.h> #include <assert.h> #include <Iphlpapi.h> #pragma comment(lib,"Iphlpapi.lib") void testLeak() { static unsigned char buf[16384]; DWORD dwSize(sizeof(buf)); if (GetIpAddrTable((PMIB_IPADDRTABLE)buf, &dwSize, false) == ERROR_INSUFFICIENT_BUFFER) { assert(0); // we never hit this branch. return; } } int main(int argc, char* argv[]) { for ( int i = 0; true; i++ ) { testLeak(); printf("i=%d\n",i); Sleep(1000); } return 0; }

  Read the article

• subscript requires array or pointer ERROR

  - by Kristian

  Hi, I know what is my mistake can't figer how to solve it. Im writing an winAPI that counts how many 'a' characters are found is a givien file. Im still getting the error " subscript requires array or pointer " (please find the comment in the code) #include "stdafx.h" #include <windows.h> int _tmain(int argc, _TCHAR* argv[]) { WCHAR str=L'a'; HANDLE A; TCHAR *fn; fn=L"d:\\test.txt"; A= CreateFile(fn,GENERIC_READ,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL); if(A==INVALID_HANDLE_VALUE) { _tprintf(L"cannot open file \n"); } else { DWORD really; int countletter; int stringsize; do { BYTE x[1024]; ReadFile(A,x,1024,&really,NULL); stringsize = sizeof(really); for(int i =0;i<stringsize;i++) { if(really[i]==str) //here Im getting the error countletter++; } }while(really==1024); CloseHandle(A); _tprintf(L"NUmbers of A's found is %d \n",countletter); } return 0; } now I know I can't make comparesion between array and a WCHAR but hw to fix it ?

  Read the article

• Getting functions of inherited functions to be called

  - by wrongusername

  Let's say I have a base class Animal from which a class Cow inherits, and a Barn class containing an Animal vector, and let's say the Animal class has a virtual function scream(), which Cow overrides. With the following code: Animal.h #ifndef _ANIMAL_H #define _ANIMAL_H #include <iostream> using namespace std; class Animal { public: Animal() {}; virtual void scream() {cout << "aaaAAAAAAAAAAGHHHHHHHHHH!!! ahhh..." << endl;} }; #endif /* _ANIMAL_H */ Cow.h #ifndef _COW_H #define _COW_H #include "Animal.h" class Cow: public Animal { public: Cow() {} void scream() {cout << "MOOooooOOOOOOOO!!!" << endl;} }; #endif /* _COW_H */ Barn.h #ifndef _BARN_H #define _BARN_H #include "Animal.h" #include <vector> class Barn { std::vector<Animal> animals; public: Barn() {} void insertAnimal(Animal animal) {animals.push_back(animal);} void tortureAnimals() { for(int a = 0; a < animals.size(); a++) animals[a].scream(); } }; #endif /* _BARN_H */ and finally main.cpp #include <stdlib.h> #include "Barn.h" #include "Cow.h" #include "Chicken.h" /* * */ int main(int argc, char** argv) { Barn barn; barn.insertAnimal(Cow()); barn.tortureAnimals(); return (EXIT_SUCCESS); } I get this output: aaaAAAAAAAAAAGHHHHHHHHHH!!! ahhh... How should I code this to get MOOooooOOOOOOOO!!! (and whatever other classes inheriting Animal wants scream() to be) instead?

  Read the article

• How does object of sub-class record information about its super-class the in a Virtual Inheritance

  - by Summer_More_More_Tea

  Hi there: I encounter this problem when tackling with virtual inheritance. I remember that in a non-virtual inheritance hierarchy, object of sub-class hold an object of its direct super-class. What about virtual inheritance? In this situation, does object of sub-class hold an object of its super-class directly or just hold a pointer pointing to an object of its super-class? By the way, why the output of the following code is: sizeof(A): 8 sizeof(B): 20 sizeof(C): 32 Code: #include <iostream> using namespace std; class A{ char k[ 3 ]; public: virtual void a(){}; }; class B : public virtual A{ char j[ 3 ]; public: virtual void b(){}; }; class C : public virtual B{ char i[ 3 ]; public: virtual void c(){}; }; int main( int argc, char *argv[] ){ cout << "sizeof(A): " << sizeof( A ) << endl; cout << "sizeof(B): " << sizeof( B ) << endl; cout << "sizeof(C): " << sizeof( C ) << endl; return 0; } Thanks in advance. Kind regards.

  Read the article

• "for" loop from program 7.6 from Kochan's "Programming in Objective-C"

  - by Mr_Vlasov

  "The sigma notation is shorthand for a summation. Its use here means to add the values of 1/2^i, where i varies from 1 to n. That is, add 1/2 + 1/4 + 1/8 .... If you make the value of n large enough, the sum of this series should approach 1. Let’s experiment with different values for n to see how close we get." #import "Fraction.h" int main (int argc, char *argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; Fraction *aFraction = [[Fraction alloc] init]; Fraction *sum = [[Fraction alloc] init], *sum2; int i, n, pow2; [sum setTo: 0 over: 1]; // set 1st fraction to 0 NSLog (@"Enter your value for n:"); scanf ("%i", &n); pow2 = 2; for (i = 1; i <= n; ++i) { [aFraction setTo: 1 over: pow2]; sum2 = [sum add: aFraction]; [sum release]; // release previous sum sum = sum2; pow2 *= 2; } NSLog (@"After %i iterations, the sum is %g", n, [sum convertToNum]); [aFraction release]; [sum release]; [pool drain]; return 0; } Question: Why do we have to create additional variable sum2 that we are using in the "for" loop? Why do we need "release previous sum" here and then again give it a value that we just released? : sum2 = [sum add: aFraction]; [sum release]; // release previous sum sum = sum2; Is it just for the sake of avoiding memory leakage? (method "add" initializes a variable that is stored in sum2)

  Read the article

• C programing fopen

  - by Pedro

  #include <stdio.h> #include <stdlib.h> typedef struct aluno{ char cabecalho[60]; char info[100]; int n_alunos; char dados[100]; char curso[100]; int numero; char nome[100]; char e_mail[100]; int n_disciplinas; int nota; }ALUNO; void cabclh(ALUNO alunos[],int a){ FILE *fp; int i; for(i=0;i<100;i++){ fp=fopen("trabalho.txt","r"); } if(fp==NULL){ printf("Erro ao abrir o ficheiro\n"); } while(!feof(fp)){ fgets(alunos[i].cabecalho,100,fp); printf("%s\n",alunos[i].cabecalho); } } fclose(fp); } what is wrong here? main: int main(int argc, char *argv[]){ ALUNO alunos[100]; int aluno; int b; cabclh(aluno,b); system("PAUSE"); return 0

  Read the article

• C++ iterator and const_iterator problem for own container class

  - by BaCh

  Hi there, I'm writing an own container class and have run into a problem I can't get my head around. Here's the bare-bone sample that shows the problem. It consists of a container class and two test classes: one test class using a std:vector which compiles nicely and the second test class which tries to use my own container class in exact the same way but fails miserably to compile. #include <vector> #include <algorithm> #include <iterator> using namespace std; template <typename T> class MyContainer { public: class iterator { public: typedef iterator self_type; inline iterator() { } }; class const_iterator { public: typedef const_iterator self_type; inline const_iterator() { } }; iterator begin() { return iterator(); } const_iterator begin() const { return const_iterator(); } }; // This one compiles ok, using std::vector class TestClassVector { public: void test() { vector<int>::const_iterator I=myc.begin(); } private: vector<int> myc; }; // this one fails to compile. Why? class TestClassMyContainer { public: void test(){ MyContainer<int>::const_iterator I=myc.begin(); } private: MyContainer<int> myc; }; int main(int argc, char ** argv) { return 0; } gcc tells me: test2.C: In member function ‘void TestClassMyContainer::test()’: test2.C:51: error: conversion from ‘MyContainer::iterator’ to non-scalar type ‘MyContainer::const_iterator’ requested I'm not sure where and why the compiler wants to convert an iterator to a const_iterator for my own class but not for the STL vector class. What am I doing wrong?

  Read the article

• Changing type of object in a conditional

  - by David Doria

  I'm having a bit of trouble with dynamic_casting. I need to determine at runtime the type of an object. Here is a demo: include include class PersonClass { public: std::string Name; virtual void test(){}; //it is annoying that this has to be here... }; class LawyerClass : public PersonClass { public: void GoToCourt(){}; }; class DoctorClass : public PersonClass { public: void GoToSurgery(){}; }; int main(int argc, char *argv[]) { PersonClass* person = new PersonClass; if(true) { person = dynamic_cast(person); } else { person = dynamic_cast(person); } person-GoToCourt(); return 0; } I would like to do the above. The only legal way I found to do it is to define all of the objects before hand: PersonClass* person = new PersonClass; LawyerClass* lawyer; DoctorClass* doctor; if(true) { lawyer = dynamic_cast(person); } else { doctor = dynamic_cast(person); } if(true) { lawyer-GoToCourt(); } The main problem with this (besides having to define a bunch of objects that won't be use) is that I have to change the name of the 'person' variable. Is there a better way? (I am not allowed to change any of the classes (Person, Lawyer, or Doctor) because they are part of a library that people who will use my code have and won't want to change). Thanks, Dave

  Read the article

• Can Boost Program_options separate comma separated argument values

  - by lrm

  If my command line is: > prog --mylist=a,b,c Can Boost's program_options be setup to see three distinct argument values for the mylist argument? I have configured program_options as: namespace po = boost::program_options; po::options_description opts("blah") opts.add_options() ("mylist", std::vector<std::string>>()->multitoken, "description"); po::variables_map vm; po::store(po::parse_command_line(argc, argv, opts), vm); po::notify(vm); When I check the value of the mylist argument, I see one value as a,b,c. I'd like to see three distinct values, split on comma. This works fine if I specify the command line as: > prog --mylist=a b c or > prog --mylist=a --mylist=b --mylist=c Is there a way to configure program_options so that it sees a,b,c as three values that should each be inserted into the vector, rather than one? I am using boost 1.41, g++ 4.5.0 20100520, and have enabled c++0x experimental extensions.

  Read the article

< Previous Page | 34 35 36 37 38 39 40 41 42 43 44 45  | Next Page >