I have objects which create other child objects within their constructors, passing 'this' so the child can save a pointer back to its parent. I use boost::shared_ptr extensively in my programming as a safer alternative to std::auto_ptr or raw pointers. So the child would have code such as shared_ptr<Parent>, and boost provides the shar...
#include <iostream> #include <string> #include <vector> #include <algorithm> using namespace std; int main(void) { string temp; vector<string> encrypt, decrypt; int i,n, co=0; cin >> n; for(i=0;i<n;i++) { cin >> temp; encrypt.push_back(temp); } for(i=0;i<n;i++) { cin >> temp...
I've all this kind of functions. ssize_t fuc1(int var1, void *buf, size_t count); int func2(char *charPtr, int mode, int dev); short func3( long var2); problem is that data types in C has different sizes when compiled on different machines(64bit & 32bit). This is true for even void*. For some reasons. I need to ensure that these siz...
I have a traits class that's used for printing out different character types: template <typename T> class traits { public: static std::basic_ostream<T>& tout; }; template<> std::ostream& traits<char>::tout = std::cout; template<> std::wostream& traits<unsigned short>::tout = std::wcout; gcc (g++) version 3.4.5 (yes somewhat old) i...
I have an application with some bunch of code like this: errCode = callMainSystem(); switch (errCode){ case FailErr: error("Err corresponding to val1\n"); case IgnoreErr: error("Err corresponding to val2\n"); ... ... default: error("Unknown error\n"); } The values are enum constants. Will it make some sense to have...
I'm trying to use the vacancy tracking algorithm to perform transposition of multidimensional arrays in C++. The arrays come as void pointers so I'm using address manipulation to perform the copies. Basically, there is an algorithm that starts with an offset and works its way through the whole 1-d representation of the array like swi...
I have a windows mobile 6 application using TAPI 2.0. lineGetAddressID() is needed to get the address identifier used by several calls in the telephone api, but I can't get it to work. I have tried the following to no avail: HLINE line; // valid handle from lineOpen(); DWORD addr_id = 0; result = ::lineGetAddressID( line, &addr_id, LIN...
void MergeSort(int A[], int n, int B[], int C[]) { if(n > 1) { Copy(A,0,floor(n/2),B,0,floor(n/2)); Copy(A,floor(n/2),n-1,C,0,floor(n/2)-1); MergeSort(B,floor(n/2),B,C); MergeSort(C,floor(n/2),B,C); Merge(A,B,0,floor(n/2),C,0,floor(n/2)-1); } }; void Copy(int A[], int startIndexA, int endI...
when we say "a member declated as protected is accessible to any class imediately derived from it" what does this mean. in the follwing example get_number function can be accessible by the result class , as per the statement it sould only be accessile to test class. class student { protected: int roll_number; public: ...
Hi guys, I have a small C++ problem to which I don't know the best solution. I have two classes A and B as follows: class A { int n; B* b; public: A(int num): n(num) { b = new B[n]; for (int i = 0; i < n; i++) { b[i].setRef(this); } } ~A() { delete [] b; } }; class...
Hello everyone :) I'm trying to speedup directory enumeration in C++, where I'm recursing into subdirectories. I currently have an app which spends 95% of it's time in FindFirst/FindNextFile APIs, and it takes several minutes to enumerate all the files on a given volume. I know it's possible to do this faster because there is an app tha...
I'm trying to make a python binding for the this library: http://code.google.com/p/hosterslib/. I'm using swig, heres is the code: %module pyhosters %{ #include "hosters/hosters.hpp" %} %include "hosters/hosters.hpp" I run swig -c++ -python -o swig_wrap.cxx swig.i and I compile with g++ -O2 -fPIC -shared ...
The standard says that dereferencing the null pointer leads to undefined behaviour. But what is "the null pointer"? In the following code, what we call "the null pointer": struct X { static X* get() { return reinterpret_cast<X*>(1); } void f() { } }; int main() { X* x = 0; (*x).f(); // the null pointer? (1) x = X::get(); ...
Consider a class Book with a stl container of class Page. each Page holds a screenshot, like page10.jpg in raw vector<char> form. A Book is opened with a path to a zip, rar, or directory containing these screenshots, and uses respective methods of extracting the raw data, like ifstream inFile.read(buffer, size);, or unzReadCurrentFile(z...
Will the following program cause any problem during compiling and execution process? class A{ public: virtual void foo(){} }; class B:public A{}; int main(){ B b; b.foo(); } ...
If I pass a value greater than 100 as the second argument to BinaryInsertionSort, I get a segmentation fault. int BinarySearch (int a[], int low, int high, int key) { int mid; if (low == high) return low; mid = low + ((high - low) / 2); if (key > a[mid]) return BinarySearch (a, mid + 1, high, key); ...
After researching this online, I've only found solutions that don't apply to my problem, so please bear with me. Code snippet: typedef map<int const *, float> my_map_t; my_map_t _test; my_map_t::const_iterator not_found = my_map_t::end(); if (_test.find(&iKeyValue) == not_found) { _test[iKeyValue] = 4 + 5; // not the actual code, but...
Basically, here's my problem. I'm calling someone else's FORTRAN functions from my C++ code, and it's giving me headaches. Some code: function c_error_message() character(len = 255) :: c_error_message errmsg(1:9) = 'ERROR MSG' return end That's the FORTRAN function. My first question is: Is there anything in there that would cause a s...
I'll get right to the point. This is what a browser request looks like GET /index.html HTTP/1.1 This is what winHTTP does GET http://site.com/index.html HTTP/1.1 Is there any I can get the winHTTP request to be the same format as the regular one? I'm using VC++ 2008 if it makes any difference ...
I'm writing a simple package manager and I'd like to automatically try sudo if the program isn't run as root. I found a function called seteuid, which looks likes it's exactly what I need, but I don't have the permissions to run it. So far all I can think of is a bash script to check before they get to the actual binary, but I'd like to ...