Here is an example,
Code:
int main()
{
try{
int y = 0;
int x = 2/y;
}
catch(...)
{
cout<<"catch it"<<endl;
}
return 0;
}
If you try, you will find out that catch(...) couldn't catch exception divided by zero. How'd we catch such exceptions?
A test program of mine loads a shared library (.so file). A function call in the shared library throws an exception that I am trying to catch in the main function of my test program. (I know that exception is being thrown for sure, I wrote the library to do that.)
However in the main program, the exception is not being caught. The flow of program goes past the catch block like no error has occurred. I am using g++ and I load the shared file using -l option. Only trying to load the program statically I got the following error:
/usr/bin/ld: cannot find -lmy-shared-library
collect2: ld returned 1 exit status
Why the exception is not getting caught.
I am working on a distributed application in C. My program gives segmentation fault and aborts execution. But, when I try to run it through gdb, it keeps on running although without giving a useful output. I realize that I do not put much information in my query. But, what general causes could generate this behaviour. I am interested to find the cause of segmentation fault.
View 8 Replies View RelatedI have this code I wrote with some data and what I'm supposed to do is insert exception handling into the code. The problem is I've seen the basic examples of it. But I don't know how to implement it into my code.
#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;
int main(){
string filename, n;
cout << "To find a file, type in the file name. " <<endl;
[Code] .....
And the file is:
A
F
D
E
U
B
V
X
M
V
there are illogical results by using try and catch block
#include<iostream>
using namespace std;
class Circle_computations {
public:
double area,circumference,radius,pi;
public:
Circle_computations() {
[Code] ....
Is it possible to develop any application without exceptions? I don't want to try and catch exceptions and remove it.but I want to write codes which should never create exceptions is it possible?
View 3 Replies View RelatedHow exactly would one go about throwing an exception from an object's constructor?
Take a look at this snippet:
#include <iostream>
#include <exception>
class ExceptionFoo : public std::exception {
virtual const char* what() const throw() {
[Code].....
I am trying to find the size of an array using a Try-Catch block. As seen on the code, I want the error to be caught when the index is out of range in "while" loop but at each time, program stops working.
int x[] = {34,5,1,536,2};
int length = 0;
int tt = 0;
try {
[Code] ....
I've been pondering which of these 2 approaches would make for the best interface for a library: Defining custom exceptions with specific names for different error scenarios but with standard behaviour, or simply using the predefined exceptions from the STL.
This is my current approach:
Code:
namespace rpp
{
class ConnectionError : public std::exception
{
public:
ConnectionError(const std::string &p_err);
[Code] .....
This seems to make for more descriptive code but it adds no functionality and the implementations are completely identical, which seems "off" to me, somehow.
The task is to use the assignment operator of a class, but change all the data except certain ones. For example, below we are to assign all Person data of 'other' except for 'name' and 'ID':
#include <iostream>
#include <string>
struct Person {
std::string name;
int ID, age, height, weight;
[Code] .....
Name = Bob
ID = 2047
Age = 38
Height = 183
Weight = 170
Name = Frank
ID = 5025
Age = 25
Height = 190
Weight = 205
Bob pretends to be Frank, but keeps his name and ID.
Name = Bob
ID = 2047
Age = 25
Height = 190
Weight = 205
But I think the way I did it is pretty lousy (note the wasted steps changing the name and ID only to revert them back? So the ideal solution should require no wasted steps, unlike the method above, and changes to what the exclusions should be should be in only one place (not two like above). Of course, we assume that Person shall have many, many data members (and constantly increasing), so that simply defining Person::operator= (const Person& other) to handle all data except for 'name' and 'ID' is out of the question.
In order to test catching exceptions from an initializer list, I deliberately did bad practice by hard coding an argument to a ctor that would cause a std::bad_allocto be thrown. Obviously better practice is to send a variable, but that would cause a compile error, so I hard coded a value.
The program I wrote creates Prime Numbers up to a specified limit which is an argument to the ctor of type std::size_t. The program works fine IMO, using g++ in cygwin:
$ time ./PrimesExe
Limit is 2000000
148933 Primes Created
real 0m1.210s
user 0m1.123s
sys 0m0.046s
Now when I send something invalid like a negative number or something too big for std::size_t, the program seems to run indefinitely, when compiled with g++ under cygwin. I haven't tested it yet on Linux.
However, if I do the same on VS2013 express, it takes about 15 seconds to print the expected caught exception message. I was not expecting it to take so ridiculously long compared to the reasonable amount of work involved in doing primes up to 2 million.
I have read up about what is involved in catching exceptions: stack unwinding, keeping track of what needs to be destroyed etc. But this is 1 object with 1 ctor argument, no Base classes or any other complications. So why such a long or indefinite amount of time?
This whole example is probably contrived, and I am wondering whether exceptions is the right tool for this - it is similar to the divide by zero problem, or could be considered a programming error to call a ctor with a bad argument?
Also, catching an exception thrown by an initalizer list seems a bit awkward in that one seems to have enclose the creation of the object and all subsequent uses of it (and any code in between ) in the same try block, otherwise it goes out scope. I suppose I could try to write a wrapper function that returns a smart pointer reference to a valid object, but I would have to test the validity of it's return too. That's the awkward part - there is probably a better way?
Are there any recommended ways of recovering from initializer list exception, that is, to allow the user to enter a new hopefully valid value and try to create the object again?
I'm Getting exceptions on Windows 7 and Windows 8 on different parts of the Code? Why this can be happening, why the difference in behavior?
View 6 Replies View RelatedI am using new operator, I don't recall what the allocator's name is. But what is the corresponding Exception (or derived classes) any try-catch block can cope with?
View 1 Replies View RelatedLet's say I want to calculate something like PI using some algorithm, but with the number of digits I want to.
View 1 Replies View RelatedConsider the following code which closes an overlapped I/O serial handle during application shutdown.
Code:
Win32Com.CancelIo(hPort);
Win32Com.CloseHandle(hPort);
It works fine under .NET 2.0 but after switching to .NET 4.0 it crashes on the CloseHandle. Removing CancelIO doesn't work.
What the correct way is to close an overlapped I/O handle? And why is there the difference between NET2.0 and 4.0?
How to handle cmd line argument in c.
View 5 Replies View RelatedI've been thinking over this for long time... For example, when a button is clicked, print a string "clicked" after 5 seconds. (the button won't be blocked)
Thread should be the only way to do this:
btn.on_click = []() {
thread thrd([]() { sleep_5_seconds(); cout << "clicked" << endl; });
thrd.start();
};
the local variable thrd is destructed right after it starts, which may cause a crash, so use new operator:
btn.on_click = []() {
thread* thrd = new thread([]() { sleep_5_seconds << "clicked" << endl; });
thrd->start();
};
The thrd never get deleted
How would you solve problem like this?
If a class A contains an array of objects of another class B.. And in the constructor of A, while constructing objects of B, any one object throws an exception, then how can we guarantee to release all the memory acquired.. so that there is no memory leak..
class B{};
class A{
public:
B Array[100];
...
};
In the above code, if in constructor of A, suppose 99 objects of B are constructed successfully, but 100th object throws exception, then how can we guarantee to release all the memory acquired by the other 99 objects?
I have a game that I'm trying to create but I don't really know how to handle mouse motions yet. I have read the LazyFoo.net lesson 9. And I have too searched around on Google but haven't find any good article for what I want to do
But what I want is to check if the mouse is OVER the START button of the game and if the user has pressed the LEFT mouse button the game should START.
This works when I am hovering over the area there I want the mouse to do something:
Code:
else if (event.type == SDL_MOUSEMOTION)
{
if (event.motion.x == 0)
{
quit = true;
}
}
I do not know how to check this. The START and QUIT button is in the middle of the screen and I don't know how to position the mouse there either.
I am using SDL 2.0. But I don't know how to handle mouse input. Do you think you can explain of how to do that? Or give me a link that explains that really great?
I know how to handle a mouse button that presses down for a sec.
Code:
if (event.type == SDL_MOUSEBUTTONDOWN){
if (event.button.button == SDL_BUTTON_LEFT){
// Do something . . .
}
}
But not how to handle the mouse input of what the mouse is hovering over and that.
Like in a start menu of a game. I want a button for example to appear blue when I hover over it and when I click on it. It should start the game for example.
I do not know any of the functions to do this, and when I looked on the internet all the functions I saw were mainly non-standard.
View 12 Replies View RelatedI have an application that uses an array of threads to call a method along with thread.join(). I was just wondering what would be the best way to handle the thread in case if one of the thread fails? Should I put a try catch block on the method that is being called or should I put the try catch block on the array of threads, or is there any other proper way to handle failed threads?
View 3 Replies View RelatedAnd it is not running successfully... abnormal termination
View 3 Replies View RelatedI write a small application and using the following API to open the file:
hHandle = CreateFile(lpszFileName, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
Then I pass the hHandle to a DLL exported function, in that function, I will call
DWORD dwFlags = 0;
ASSERT(GetHandleInformation(hFile,&dwFlags) != 0)
to check if the handle is valid. However, the assert fails. And I use GetLastError to get the error code 6, which means invalid handle.
What is the problem with my codes?
Visual C++ 2010
I'm using SFML with Visual C++ and need to pass a handle to a function. I've tried to find this on the web with no luck.
The handle happens to be a sprite defined as: sf::Sprite Numbers(MyNumbers);
Now I want to pass "Numbers" to a function.
-
-
getFrame(Numbers);
-
-
???? getFrame(??????) {
Numbers.SetSubRect(sf::IntRect(0,0,63,63));
return ????
}
How do I do this?
I have an MFC program created from the app wizard. It is an MDI program, reading/writing text files using Serialize. I can read the document and know that the entire document was read into my buffer without any errors. This was verified by compaing the number of bytes read with the file length.
How do I get the document to display in my main/child window?
How do I read the document from the window so I can save it back to the file?