I want to know how mutex is working in process synchronization. Where these mutexes are stored in memory how another process know about this mutex?
If two different mutexes are having same name what will happen?
I'm trying figure out how Windows Firewall functions by experimenting with Bittorrent's add exception to windows firewall option, I deleted the entry from the Firewall options and also located that the regkeys are in HKLM/System/CurrentControlSet/Services/SharedAccess/Parameters/FirewwallPolicy but I can't figure out what registries are made when an application is added as an exception in the Windows Registry.
View 6 Replies View RelatedJust now I started learning Windows services.I want to create a windows Service that will call the stored procedure every 30 days.
View 1 Replies View RelatedIf any exception occurs in critical section code then what sort of issue which we see in terms of synchronization objects?
Before and after the critical section code, Mutex is locked and unlocked. But if any exception occurs then the waiting thread will be waiting for resource to be freed as Mutex is not unlocked due to the exception.
I've verified this on ubuntu 12.10 and on windows/mingw, and found that g++ version 4.7.2 seems to have broken thread/mutex support.
View 11 Replies View RelatedI was trying to put mutex lock on shared memory but my code is not working. What I want is that if some process is putting something on shared memory segment, other process should not be able to access that segment. For testing , I create a server program which put data in shared memory and client program which access the data.
To test it, I put break point after:
pthread_mutex_lock(&(init_lock));
But I see that client program was able to access shared memory.
Below is code:
Server: Code: pthread_mutex_t init_lock = PTHREAD_MUTEX_INITIALIZER;
main()
{
char c;
[Code].....
Consider how to implement a mutex lock using an atomic hardware instruction. Assume that the following structure defining the mutex lock is available:
Code:
typedef struct {
int available;
}
lock; (available == 0)
indicates that the lock is available, and a value of 1 indicates that the lock is unavailable. Using this struct, illustrate how the following functions can be implemented using the test and set() and compare and swap() instructions:
void acquire(lock *mutex)
void release(lock *mutex)
Be sure to include any initialization that may be necessary.
How do you use a stored procedure with a WebGrid? Our coding standard say we cannot write sql statement directly in the code to include HTML.
[var Grid = new WebGrid(DB.Query("Select * from Menu")]
The above call must be a call to a stored procedure.
I am/we developing in C and we have a number of different programs. We also have problem to keep track of different versions of a specific exe file.
Is there any way to add version number when build a file so the version is added in the properties.
I doing this in a MFC c++ project in a .rc file. Is there a way (or a similar way) of doing this in C? Here its stored in the details section with product version 6.0.8:
I know that memory addresses in the stack can contain either values or references to other memory addresses, but do these memory addresses also contain methods or are the methods themselves located in the heap?
The confusion comes from the fact that in C# a delegate variable can be assigned either a method's identifier, an inline function, a lambda expression, or a new instance of the delegate type with the method's identifier passed as an argument to the constructor. My guess is that assigning the method's identifier directly to the delegate variable is just a simplified way of calling the delegate type's constructor with the method's identifier as an argument to the parameter, something that the compiler handles for you.
But even in this last case, the delegate variable is said to point toward the method itself. In that case, does it mean that methods are stored in the heap, just as reference type values are?
when i compile and run it it gives me the number 0 and not the proper number stored in array.
Code:
#include <stdio.h>
int main()
{
int myArray[11] = { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5 };
}
[code]....
For example when I have:
Class A{
B objectB;
};
Now when I instantiate the object of class A like:
main(){
A objectA;//option 1
A* pObjectA = new A();// option2
}
How is objectB stored in memory (stack heap etc.) for both options??
Making a game of checkers on C++ win32, visual studio
when i want a piece to move, i type:
cout << "What piece do you want to move? (C4)" << endl;
i type in 'cin' after to get the players input, but how do i get it to store the players input in a certain variable? im going to have a list of variables:
string a1
string a2
string a3
etc
so if the user types in a2, it automatically goes to that variable and then asks the user "where do you want the piece to be moved to?".
So I'm trying to delete a value stored inside one of my vectors but I can't accomplish this. My attempts are down below. I've commented out one attempt since it gives me errors. How can I do what I am trying to do?
#include <iostream>
#include <vector>
using namespace std;
int main() {
vector<vector<int> >row;
vector<int> newColumn;
[Code] ....
Reposting this as I deleted my pervious post because I missed out some parts of the codes.
I am trying to read a textfile containing some informations in this format,I am able to extract everything except the itemId.
I am trying to build a employee management system using C, and I have done alot so far. Everything seems to work fine, but then I thought that I should let the user store the data of their employees permanently, therefore I created a file and then I store the user's given data in the txt file.
Here is the code:
#include<stdio.h>
#include<conio.h>
#include<string.h>
[Code].....
But there is some problem, and I don't seem to understand what is the problem in the code, it's just that whenever the user enters any id to search, and presses any key then nothing appears just a blank screen! I wanted to know that how can I check the ID from the text file and then display the details of the employee of that id!
I have a table in my database that has a 3 fields.
RuleID | RuleName | Rule
the ruleID is a randomly generated string of characters, RuleName is the name the user gives to the rule, and the Rule field is about 600 characters long and is just XML text.
I want to read that Rule field from the database and use it inside the function below.
private static List<MenuItem> LoadRules(bool evaluationType)
{
//string path = HttpContext.Current.Server.MapPath(string.Format("/Rules/{0}/{1}/", ip, evaluationType ? "Evaluation" : "Execution"));
[Code]...
This function loads an xml file from a static location and parses out some information to a context menu.
BUt i'm culeless on how to have the function read the xml info found inside my database.
I want to declare a char* array, and then make any future variables declared to be stored in a specific location within the char* array. Is this even possible, and if it is how would I go about doing it. (I plan on storing any primitive data type in it (not classes or structs), and they may signed or unsigned).....
View 12 Replies View RelatedFor my code, I want the user to enter 4 integers, which get stored in an array. Here are the lines I wrote relevant to this part:
Code:
printf("Enter 4 integers:
");
scanf("%d %d %d %d," &a, &b, &c, &d);
z[4] = { a, b, c, d};
Would this be correct?
I am trying to compare a string that i have entered with a set of strings that have already been stored in a file. I am using strcmp function but i am not getting the result.
Code:
printf("
Enter string:");
scanf("%s",&m);
ptr_file =fopen("abc.text","r");
[Code] .....
I am writing a C program to access a string into an array from a pointer array in Visual Studio 2010. Program is given below:-
Code:
#include <stdio.h>
#include <string.h>
void main() {
char data_a[6],data_b[6]="ABcde",*ptr;
ptr=&data_b[0];
data_a[0]=*ptr;
printf("%s",a);
}
I am getting some junk character first and then my actual data on console window. I want to where I am getting wrong and how to resolve it.
how to save text stored in an array to a txt file. can sum1 how to save the text in an array to a file/txt file......
View 7 Replies View RelatedSo, if I'm right, computer store their data as binary values. So if I write int x = 5; , my computer converts the value of x from decimal (5) into binary (101) and stores it in memory as a a binary number. If I print that value on the screen that value is converted(by default) back into a decimal number before being printed on the screen.
Now, my question is if there is any way to print the value of x directly into binary(as it's stored in memory) without it being converted back into a decimal value?
I've got a VERY experimental function which takes data stored to a file and assigns it to a multidimensional array on the heap. It's designed for infinite dimensions by recalling itself with updated information but I don't think this is very safe.
The template function creates a heap array using a TYPE**, and recalls itself to create the new dimensions. I want to replace this with the much safer method of assigning just a single heap memory array and then only assign using the recalling method (unless I can find anything else).
To do this though I need to know how single dimensional arrays are stored on the heap, as well as multi-dimensional (for n dimensions). Where I can find this information?
btw I only need this for the Windows operating system, 32bit, I'm not exactly sure what 'C++ style' this is but I'm using Microsoft's Visual Studio Express 2012 as my IDE, so whatever that uses.
my doubt is :- in what data type the intermediate result of an expression is stored? like for expression 2+3*1/2 , i think the intermediate result for 1/2 is stored in the form 0.5 but for expression 2+3*1/100 , i think the intermediate result for 1/100 is stored in the form 0.01 so i am not sure if the compiler use dynamic type ie, changes with need. or it always stores in high precision like:- for 1/2 its 0.5000 and for 1/100 also 0.0100 or something like that.
View 4 Replies View RelatedHow do I compare multiple datas?
I have climate data for 6 months and is trying to find the highest climate month among all 6 months. How do I do that?