Hi, I'm working on a simulation that uses multithreading extensively. The thing is that, until now i've never used any mutex objects to protect my data. And the result, is that i'm getting bunch of segmentation faults.. I'm trying to lock/unlock with mutex while : reading/writing but that causes me another segfault : #0 77D27DD2 ntdl...
Working through more book examples- this one is a partial poker program- This segment deals with straight hand.... First what was given- only relevant parts....will provide entire code if needed... int suits[5]; //index 1..4- value start at 1 int values[14]; //index 1..13- value same as rank, A = 1, K = 13 cin.get(rankCh); switch (toU...
time_t seconds; time(&seconds); cout << seconds << endl; This gives me a timestamp. How can I get that epoch date into a string? std::string s = seconds; does not work Thanks, Noah P.S. It's really much easier in ruby!: >> Time.now.to_i.to_s => "1245089994" ...
Hey Folks i am trying to compile this C++ program: #include <stdio.h> #include <string.h> #include <sys/stat.h> #include <stdlib.h> #include <Windows.h> #include "Validate.h" JNIEXPORT jstring JNICALL Java_Validate_takeInfo(JNIEnv *env, jobject obj, jstring domain, jstring id, jstring idca, jstring password) { const c...
I am trying to read in a scanned image and compress it from a DIB in memory into a TIF file. I am using the libtiff library and have found a couple examples online but none of them really do as I need them to. I need to take the image from the DIB and turn it into a B&W image. Here is the code I have modified from an online example. It ...
I'm trying to compile a very simple C application using VS2008. My problem is that the resultant binary requires systems to have .NET installed. No actual code within the project uses .NET functionality, but I get errors during execution on any system that doesn't have .NET. So, is there anyway to compile using VS2008 so the resultant ...
Q1. What happens first- memory allocation or constructor call for the below written statement ? int *ptr = new int(); Q2. What is the difference between following three approaches? If an object is destroyed with DELETE operator. Will destructor be called? If a destructor is called explicitly (e.g. a1.~A()) to destroy the object? Nei...
I'm trying to make a function that takes a character, then returns a pointer to a function depending on what the character was. I just am not sure how to make a function return a pointer to a function. ...
I thought I bookmarked a post on C++ best practices but I cannot seem to find it. The title was something like, "10 things you should not do in C++", or something along those lines. One recommendation was to not declare variables at the top of a function, but only when they are first needed. Another was not adding parameters to constr...
While a send() succeeds with all data being sent most of the time, it is not always the case. Thus people are advised to use the write-fdset for select() and poll() to check when the socket is writeable. How do usual mechanisms look like to actually buffer the data to send while still maintaining a well comprehensible sourcecode? ...
Hello, is there a crossplatform way to get current date and time in c++? Thanks. ...
I am looking for a way to branch (tee) the input read from an istream (cin, in my case) out to a log file (clog/ofstream/etc), while still using the input for processing. I have read about boost::tee_device, and it is very similar to my requirements. Unfortunately, it is implemented as an ostream, and thus solves a similar problem from...
I wrote a program for linux using libxml2 for html parsing. Although it does its job, the html parser writes lots of various errors to stderr. Is it possible to disable stderr at all (or redirect it to /dev/null while not having to run it with a redirecting shell script)? I can live with having to write my own errors to stdout, I just wa...
When static members are inherited, are they static for the entire heirarchy, or just that class, ie: class SomeClass { public: SomeClass(){total++;} static int total; }; class SomeDerivedClass: public SomeClass { public: SomeDerivedClass(){total++;} }; int main() { SomeClass A; SomeClass B; SomeDerivedClass C; ...
I'm developing an embedded application using GCC/G++ compiled for arm-eabi. Due to resource constraints, I'm trying to disable the standard C++ exception handling. I'm compiling the code with "-fno-exceptions -nostartfiles -ffreestanding". When a global instance of a class exists, and that class contains an instance of another class ...
EDIT: declaring them private was a typo, I fixed it: Relating to another question, if I declared a static variable in a class, then derived a class from that, is there any way to declare the static variable as individual per each class. Ie: class A: { public: static int x; }; class B:A { public: const static int x; }; does that defi...
See subject. What were they thinking? UPDATE: Changed from "static" to "internal linkage" to save confusion. To give an example... Putting the following in a file: const int var_a = 1; int var_b = 1; ...and compiling with g++ -c test.cpp only exports var_b. ...
I'm using OpenCV for object detection and one of the operations I would like to be able to perform is a per-pixel square root. I imagine the loop would be something like: IplImage* img_; ... for (int y = 0; y < img_->height; y++) { for(int x = 0; x < img_->width; x++) { // Take pixel square root here } } My question is how can...
I am trying to write a C++ template function that will throw a runtime exception on integer overflow in casts between different integral types, with different widths, and possible signed/unsigned mismatch. For these purposes I'm not concerned with casting from floating-point types to integral types, nor other object-to-object conversions...
When you enter a space ' ' while typing into cin, it will take the first string before the space as the first value and the later one as the next. So let's say we have this code: cout << "Enter your Name"; cin >> name; cout << "Enter your age"; cin >> age; Now, let's say a user enters "John Bill". It would take his name to be John ...