Search Results

Search found 3887 results on 156 pages for 'pointer arithmetic'.

Page 45/156 | < Previous Page | 41 42 43 44 45 46 47 48 49 50 51 52  | Next Page >

• Installing Ruby 1.8.6 via RVM on Snow Leopard

  - by Neil Middleton

  I'm trying to install ruby 1.8.6 onto Snow Leopard - but am getting some make errors: ossl_x509revoked.c: In function ‘ossl_x509revoked_new’: ossl_x509revoked.c:48: warning: passing argument 2 of ‘ASN1_dup’ from incompatible pointer type ossl_x509revoked.c: In function ‘DupX509RevokedPtr’: ossl_x509revoked.c:64: warning: passing argument 2 of ‘ASN1_dup’ from incompatible pointer type readline.c: In function ‘username_completion_proc_call’: readline.c:730: error: ‘username_completion_function’ undeclared (first use in this function) readline.c:730: error: (Each undeclared identifier is reported only once readline.c:730: error: for each function it appears in.) make[1]: *** [readline.o] Error 1 make: *** [all] Error 1 Anyone have any ideas?

  Read the article

• Calling a native callback from managed .NET code (when loading the managed code using COM)

  - by evilfred

  Hi, I am really confused by the multitude of misinformation about native / managed interop. I have a C++ exe which is NOT built using CLR stuff (it is not Managed C++ or C++/CLI and never will be). I would like to access some code I have in a C# assembly. I can access the C# assembly using COM. However, when my C# code detects an event I would like it to call back into my C++ code. The C++ function pointer to call back into will be provided at runtime. Note that the C++ function pointer is a function found in the exe's execution environment. I don't want the managed code to try and load up some DLL to call a function (there is no DLL). How do I pass this C++ function pointer to my C# code through .NET and have my C# code successfully call it? Thanks!

  Read the article

• Integrate Cppcheck with Emacs

  - by N.N.

  Is it possible to integrate Cppcheck with Emacs in a more sophisticated way than simply calling the shell command on the current buffer? I would like Emacs to be able to parse Cppcheck's messages and treat them as messages from a compiler (similar to how compile works), such as using C-x ` to visit the targets of Cppcheck's messages. Here is some example output Cppcheck: $ cppcheck --enable=all test.cpp Checking test.cpp... [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 5 [test.cpp:38]: (style) The scope of the variable 'i' can be reduced [test.cpp:38]: (style) Variable 'i' is assigned a value that is never used [test.cpp:23]: (error) Possible null pointer dereference: p [test.cpp:33]: (error) Possible null pointer dereference: p Checking usage of global functions.. [test.cpp:36]: (style) The function 'f' is never used [test.cpp:1]: (style) The function 'f1' is never used [test.cpp:9]: (style) The function 'f2' is never used [test.cpp:26]: (style) The function 'f3' is never used

  Read the article

• 32bit to 64bit inline assembly porting

  - by Simone Margaritelli

  I have a piece of C++ code (compiled with g++ under a GNU/Linux environment) that load a function pointer (how it does that doesn't matter), pushes some arguments onto the stack with some inline assembly and then calls that function, the code is like : unsigned long stack[] = { 1, 23, 33, 43 }; /* save all the registers and the stack pointer */ unsigned long esp; asm __volatile__ ( "pusha" ); asm __volatile__ ( "mov %%esp, %0" :"=m" (esp)); for( i = 0; i < sizeof(stack); i++ ){ unsigned long val = stack[i]; asm __volatile__ ( "push %0" :: "m"(val) ); } unsigned long ret = function_pointer(); /* restore registers and stack pointer */ asm __volatile__ ( "mov %0, %%esp" :: "m" (esp) ); asm __volatile__ ( "popa" ); I'd like to add some sort of #ifdef _LP64 // 64bit inline assembly #else // 32bit version as above example #endif But i don't know inline assembly for 64bit machines, anyone could help me? Thanks

  Read the article

• Functions as pointers in Objective-C

  - by richman0829

  This is a question from Learn Objective-C on the Mac... Functions as pointers What I typed in, as per the recipe, was: NSString *boolString (BOOL yesNo) { if (yesNo) { return (@"YES"); } else { return (@"NO"); } } // boolString The pointer asterisk in the first line doesn't seem necessary, yet deleting it results in an error message. But what does it do? In NSString * boolString (yesNo); what seems to be going on is a function is defined as a pointer to an NSString. The function without the asterisk NSLog (@"are %d and %d different? %@", 5, 5, boolString(areTheyDifferent)); returns an NSString of YES or NO. But how can it return an NSString when it's a pointer? It might return the ADDRESS of an NSString; or if dereferenced it could return the CONTENTS of that address (an NSString such as YES or NO). Yet I see no place where it is dereferenced.

  Read the article

• Change compilation flags in Qt under Mac OS X?

  - by Lior

  I installed Qt for Mac, and am compiling my Qt project after adding in the .Pro file CONFIG(release, debug|release):QMAKE_CXXFLAGS += -O3 -fomit-frame-pointer to optimize for speed. However, I always see that the command where g++ is ran, includes -Os, which optimizes for size. I would like to remove it. I tried several approaches, like CONFIG(release, debug|release):QMAKE_CFLAGS_RELEASE -= -Os CONFIG(release, debug|release):QMAKE_CXXFLAGS -= -Os and CONFIG(release, debug|release):QMAKE_CXXFLAGS = -O3 -fomit-frame-pointer CONFIG(release, debug|release):QMAKE_CFLAGS_RELEASE = -O3 -fomit-frame-pointer (no +) But nothing. -Os ALWAYS appear. How do I change this? I found the qmake.conf file under /usr/local/QT4.5/mkspecs. It includes a mac-g++.conf file, but I cannot change it, and chmod doesn't work: chmod: mac-g++.conf: Operation not permitted Any ideas?

  Read the article

• What does subl do here?

  - by drozzy

  So... I'm compiling into assembler, with gcc -S -O2 -m32: void h(int y){int x; x=y+1; f(y); f(2); } And it gives me the following: .file "sample.c" .text .p2align 4,,15 .globl h .type h, @function h: pushl %ebp movl %esp, %ebp subl $24, %esp movl 8(%ebp), %eax movl %eax, (%esp) call f movl $2, 8(%ebp) leave jmp f .size h, .-h .ident "GCC: (GNU) 4.4.3 20100127 (Red Hat 4.4.3-4)" .section .note.GNU-stack,"",@progbits Now I know what pushl and movel: they store the current frame pointer onto the stack and then set the value of the frame pointer register to the value of the Stack Pointer. But I have no idea what the subl $24, %esp is. Thanks!

  Read the article

• Loading an OverlayView from XIB -vs- programmatically for use with UIImagePickerController

  - by PLG

  I am currently making a camera app for iPhone and I have a strange phenomenon that I can't figure out. I would appreciate some help understanding. When recreating an overlay view for passing to UIImagePickerController, I have been successfully been able to create the view programmatically. What I haven't been able to do is create the view with/without controller in IB, load it and pass it to the overlay pointer successfully. If I do it via IB, the view is not opaque and obscures the view of the camera completely. I can not figure out why. I was thinking that the normal view pointer might be assigned when loading from XIB and therefore overwrite the camera's view, but I have an example programmatically where view and overlayView are set equal in the controller class. Perhaps the load order is overwriting a pointer? Help would be appreciated... kind regards.

  Read the article

• Implementing callback functions in C

  - by robertjohn123

  Hi, I am a newbie to C.I am trying to implement callback function using function pointers. I am getting an error :test_callback.c:10: error: expected identifier or ‘(’ before ‘void’ when I try to compile the following program: #include<stdio.h> void (*callback) (void); void callback_proc () { printf ("Inside callback funtion\n"); } void register ((void (*callback) (void))) { printf ("Inside registration \n"); callback (); /* Calling an initial callback with function pointer */ } int main () { callback = callback_proc;/* Assigning function to the function pointer */ register (callback);/* Passing the function pointer */ return 0; } What is this error?Can anyone help?

  Read the article

• Are indivisible operations still indivisible on multiprocessor and multicore systems?

  - by Steve314

  As per the title, plus what are the limitations and gotchas. For example, on x86 processors, alignment for most data types is optional - an optimisation rather than a requirement. That means that a pointer may be stored at an unaligned address, which in turn means that pointer might be split over a cache page boundary. Obviously this could be done if you work hard enough on any processor (picking out particular bytes etc), but not in a way where you'd still expect the write operation to be indivisible. I seriously doubt that a multicore processor can ensure that other cores can guarantee a consistent all-before or all-after view of a written pointer in this unaligned-write-crossing-a-page-boundary situation. Am I right? And are there any similar gotchas I haven't thought of?

  Read the article

• How to debug/reformat C printf calls with lots of arguments in vim?

  - by Costi

  I have a function call in a program that I'm maintaining has 28 arguments for a printf call. It's printing a lot of data in a CSV file. I have problems following finding where what goes and I have some mismatches in the parameters types. I enabled -Wall in gcc and I get warnings like: n.c:495: warning: int format, pointer arg (arg 15) n.c:495: warning: format argument is not a pointer (arg 16) n.c:495: warning: double format, pointer arg (arg 23) The function is like this: fprintf (ConvFilePtr, "\"FORMAT3\"%s%04d%s%04d%s%s%s%d%s%c%s%d%c%s%s%s%s%s%s%s%11.lf%s%11.lf%s%11.lf%s%d\n", some_28_arguments_go_here); I would like to know if there is a vim plugin that highlights the printf format specifier when i go with the cursor over a variable. Other solutions? How to better reformat the code to make it more readable?

  Read the article

• string parsing and substring in c

  - by Josh

  I'm trying to parse the string below in a good way so I can get the sub-string stringI-wantToGet: const char *str = "Hello \"FOO stringI-wantToGet BAR some other extra text"; str will vary in length but always same pattern - FOO and BAR What I had in mind was something like: const char *str = "Hello \"FOO stringI-wantToGet BAR some other extra text"; char *probe, *pointer; probe = str; while(probe != '\n'){ if(probe = strstr("\"FOO")!=NULL) probe++ else probe = ""; // Nulterm part if(pointer = strchr(probe, ' ')!=NULL) pointer = '\0'; // not sure here, I was planning to separate it with \0's } Any help will be appreciate it.

  Read the article

• Reallocating memory via "new" in C++

  - by BSchlinker

  Quick question regarding memory management in C++ If I do the following operation: pointer = new char [strlen(someinput_input)+1]; And then perform it again, with perhaps a different result being returned from strlen(someinput_input). Does this result in memory being left allocated from the previous "new" statement? IE, is each new statement receiving another block of HEAP memory from the OS, or is it simply reallocating? Assuming I do a final delete pointer[]; will that deallocate any and all memory that I ever allocated via new to that pointer? Thanks

  Read the article

• Array of strings and char ** environ variable.

  - by Naruto Uzumaki

  Hello! I want to know how an array of strings is declared? What I do is I declare an array of pointers of pointers to strings. Eg. char *array[]= {"string1","string2","string3"}; I was reading about modifying environment variables in Linux and stumbled upon the pointer char **environ ( http://www.cs.bham.ac.uk/resources/courses/2005/17423/doc/libc/Environment-Access.html#Environment-Access ). char **environ is declared as an array of strings. I think it should be a pointer to a pointer. For eg. char *array[]= {"string1","string2","string3"}; environ = array; Am I doing something wrong? I also read somewhere that char *argv[] = char **argv. How is it possible?

  Read the article

• Adding animation to my images with JQuery

  - by slandau

  Here is my home page: <%@ Page Language="C#" MasterPageFile="~/Views/Home/Home.Master" Inherits="System.Web.Mvc.ViewPage" %> <asp:Content ID="Content2" ContentPlaceHolderID="IndicationContentPlaceHolder" runat="server"> <table id="home" style="margin-left: auto; margin-right:auto;"> <td id="homeLinks"> <div style="padding-left:35px;" id="homeListing" class="containerMid"> <div id="homeView"> <table style="margin-left: auto; margin-right:auto;"> <tr> <tr> <td id="btnIcOld" style="text-align:center;cursor:pointer;"> <img src="<%= VirtualPathUtility.ToAbsolute("~/img/chic/Load.png")%>" /> </td> <td id="btnIc" style="text-align:center;cursor:pointer;"> <img src="<%= VirtualPathUtility.ToAbsolute("~/img/chic/Bar_Chart.png")%>" /> </td> <td id="btnPricing" style="text-align:center;cursor:pointer;"> <img src="<%= VirtualPathUtility.ToAbsolute("~/img/chic/Pie_Chart_disabled.png")%>" /> </td> <td id="btnSheets" style="text-align:center;cursor:pointer;"> <img src="<%= VirtualPathUtility.ToAbsolute("~/img/chic/Line_Chart_disabled.png")%>" /> </td> <td id="btnPort" style="text-align:center;cursor:pointer;"> <img src="<%= VirtualPathUtility.ToAbsolute("~/img/chic/Modify_disabled.png")%>" /> </td> <td id="btnAdmin" style="text-align:center;cursor:pointer;"> <img src="<%= VirtualPathUtility.ToAbsolute("~/img/chic/Profile_disabled.png")%>" /> </td> </tr> <tr> <td id="Td1"> <b>Indications Calculator | </b> </td> <td id="lblIc"> <b>Indications Calculator - Beta | </b> </td> <td id="lblPricing"> <b>Managing Pricing Triggers | </b> </td> <td id="lblSheets"> <b>Creating Pricing Sheets | </b> </td> <td id="lblPort"> <b>Portfolio Analysis | </b> </td> <td id="lblAdmin"> <b>Administration</b> </td> </tr> </tr> </table> </div> </div> </td> </table> <div id="pageMessage"></div> <script> $(document).ready(function () { $('#btnIc').live('click', function () { window.location.href = "<%=Url.Action("Indications") %>"; }); $('#btnIcOld').live('click', function () { window.location.href = 'https://extranetint/swap'; }); $('#btnPricing').live('click', function () { //window.location.href = "<%=Url.Action("Triggers") %>"; }); $('#btnSheets').live('click', function () { //window.location.href = "<%=Url.Action("Sheets") %>"; }); $('#btnPort').live('click', function () { //window.location.href = "<%=Url.Action("Analysis") %>"; }); $('#btnAdmin').live('click', function () { //window.location.href = "<%=Url.Action("Admin") %>"; }); }); </script> </asp:Content> How can I, with JQuery (or really anything), achieve a mouse-over effect on my images where they will grow a little bit as you hover over them? I tried using JQuery animate but for some reason I couldn't get it to work. Thanks!

  Read the article

• exporting non_public type through public API

  - by user329820

  Hi I have written this code in Netbeans but it will show this warning for the name of this method ,would you please help me for what it shows this warning? thanks public Node returnNode(int index) throws IndexOutOfBoundsException { if (index < 0 || index > size) { throw new IndexOutOfBoundsException(); } else { for (int i = 0; i < index; i++) { pointer = pointer.getNext(); } } return pointer; }

  Read the article

• [c]how to take input for a character pionter without using fget?

  - by ashish yadav

  consider the code include int main() {char* a; scanf("%s",a);//&a and &a[0] give same results-crashes printf("%s",); return 0; } why does this code results in crashing?whereas this code using character array works fine? include int main() {char a[100]; scanf("%s",&a[0]);//works fine printf("%s",a); return 0; } the difference being character array and pointer?but i knew that pointer just points to the first element that is &a[0] should work fine but upper code crashes for all three that is a,&a and &a[0]? the main thing i would to gather is how can i take input of a character pointer if i insist on using scanf only? i apologize if i am not clear. thanks in advance:)

  Read the article

• Best way to call other class view in iphone?

  - by aman-gupta

  Hi, Generally i call my other class view by creating a pointer of delegate and then call the other class by using its link as below:- First Way :- Mydelegate *ptr = (Mydelegate *)[[UIApplication sharedApplication]delegate]; [self.navigationController pushViewController:ptr.NextClasspointer animated:YES]; Second Way :- Create a pointer of that class which u want to call :-- NextClass *nextptr = [[NextClass alloc]initWithnibName:@"NextClass" bundle:nil]; [self.navigationController pushViewController:nextptr animated:YES]; [nextptr release]; nextptr = nil; These above two methods i generally used but my problem is that which one is best for big project so that my stack problem will be removed I mean memory issue will be solved.And is it necessary to release pointer in first and second case is the way i release is correct or wrong Please help me Thanks in Advance

  Read the article

• The ** idiom in C++ for object construction

  - by bobobobo

  In a lot of C++ API'S (COM-based ones spring to mind) that make something for you, the pointer to the object that is constructed is usually required as a ** pointer (and the function will construct and init it for you) You usually see signatures like: HRESULT createAnObject( int howbig, Object **objectYouWantMeToInitialize ) ; -- but you seldom see the new object being passed as a return value. Besides people wanting to see error codes, what is the reason for this? Is it better to use the ** pattern rather than a returned pointer for simpler operations such as: wchar_t* getUnicode( const char* src ) ; Or would this better be written as: void getUnicode( const char* src, wchar_t** dst ) ; The most important thing I can think of is to remember to free it, and the ** way, for some reason, tends to remind me that I have to deallocate it as well.

  Read the article

• Access to bytes array of a Bitmap

  - by Deulis

  1- In Windows CE, I have a Bitmap object in C#. 2- I have a C function in an extern dll that expects as parameters the pointer to a bytes array that represents an image in RGB565 format, width and height. This function will draw on this array of bytes. So I need to pass the byte array pointer of the Bitmap object, but I can find a practical way to get this pointer. One way is convert this Bitmap into a bytes array using a memory stream or something else, but it will create a new bytes array, so I will keep in memory both object, the Bitmap and the bytes array, but I don’t want it because the few available memory, that’s why I need to access to the bytes array of the bitmap object, not create a new bytes array. Anyone can help me?

  Read the article

• C++: static function member shared between threads, can block all?

  - by mhambra

  Hi all, I have a class, which has static function defined to work with C-style extern C { static void callback(foo bar) { } }. // static is defined in header. Three objects (each in separate pthread) are instantiated from this class, each of them has own loop (in class constructor), which can receive the callback. The pointer to function is passed as: x = init_function(h, queue_id, &callback, NULL); while(1) { loop_function(x); } So each thread has the same pointer to &callback. Callback function can block for minutes. Each thread object, excluding the one which got the blocking callback, can call callback again. If the callback function exists only once, then any thread attempting to callback will also block. This would give me an undesired bug, circa is interesting to ask: can anything in C++ become acting this way? Maybe, due to extern { } or some pointer usage?

  Read the article

• C++: Question about freeing memory

  - by Martijn Courteaux

  On Learn C++, they wrote this to free memory: int *pnValue = new int; // dynamically allocate an integer *pnValue = 7; // assign 7 to this integer delete pnValue; pnValue = 0; My question is: "Is the last statement needed to free the memory correctly, completly?" I thought that the pointer *pnValue was still on the stack and new doesn't make any sense to the pointer. And if it is on the stack it will be cleaned up when the application leaves the scope (where the pointer is declared in), isn't it?

  Read the article

• Is void *p = 0L valid?

  - by Artefacto

  In this answer, sassman initializes a pointer with: zend_class_entry* ce = 0L; My question is – is this valid? I would say it isn't, to initialize the variable with a null pointer either an unadorned (and possibly casted to void *) 0 constant, or some macro that evaluates to that such as NULL should be used. However, I can't find definitive language in the standard that supports this interpretation. All it says is: An integer constant expression with the value 0, or such an expression cast to type void *, is called a null pointer constant.

  Read the article

• Determine an object's class returned by a factory method (Error: function does not take 1 arguments

  - by tzippy

  I have a factorymethod that either returns an object of baseclass or one that is of derivedclass (a derived class of baseclass). The derived class has a method virtual void foo(int x) that takes one argument. baseclass however has virtual void foo() without an argument. In my code, a factory method returns a pointer of type bar that definetly points to an object of class derivedclass. However since this is only known at runtime I get a compiler error saying that foo() does not take an argument. Can I cast this pointer to a pointer of type derivedclass? std::auto_ptr<baseclass> bar = classfactory::CreateBar(); //returns object of class derivedclass bar->foo(5); class baseclass { public: virtual void foo(); } class derivedclass : public baseclass { public: virtual void foo(int x); }

  Read the article

• in c++ what is bettr to delete poiner or set it with new value?

  - by user63898

  Hi simple question in c++ , say i have a loop and i have function that returns pointer to item so i have to define inner loop pointer so my question is what to do with the pointer inside the loop , delete it ? or to set it with new value is good for example: for(int i =0;i<count();i++) { ptrTmp* ptr = getItemPtr(); // do somthing with the ptr ... // what to do here ? to delete the poinetr or not? delete ptr; // ?? }

  Read the article

< Previous Page | 41 42 43 44 45 46 47 48 49 50 51 52  | Next Page >