C :: Code That Will Store PID Numbers Of Child After A Fork?
Aug 8, 2013
I am currently trying to write a code that will store PID numbers of a child after a fork, I have to be able to enter an amount that will be created, so far I have managed to be able to get them to print (which puts me on the right path as far as I am concerned) but I am having issues. Using the following code:
Find all the prime numbers between a given pair of numbers. Numbers should be read in from an input file called "numbers.txt" and find all the prime numbers between them. Store the prime numbers in an array, then sort the array from greatest to least. Display the array before and after the sort.
I'm stuck on how to put the prime numbers into an array.
The input file has the numbers 1 & 100.
Here's what I have so far.
#include <iostream> #include <fstream> using namespace std; int main() { ifstream fin; fin.open("numbers.txt");
what I'm trying to do is create 3 child processes stemming from one parent process. I have figured that out but the problem is my program exits when it get to the third child leaving it orphaned(I think).
This is my code for the first generation of processes:
int i = 0; pid_t child; about("Dad"); printf("Now .. Forking !!
[Code] .....
I have created a menu GUI that I feel messes with the loop commands, i.e. "Continue". The menu pops up repeatedly after each child process is created. I commented out the block of code for menu which fixed it. I was wondering if there is a way so that I can have the menu not messing with the processing?
How can I implement the paradigm demonstrated by the code below to run on WinXP?
I want to fork a process or create a thread that shares global variables with the parent process/thread.
The child process/thread monitors the progress of the parent process/thread.
I cannot find documentation for a fork function per se, a Unix term. It might be called something different for WinXP.
I would be happy to use threads instead. But I'm rusty even with Unix application threads; and I know nothing of WinXP application threads.
So any turnkey implementation that demonstrates the simplest use of process or thread functions for my purpose demonstrated below.
In either case, do "forked" processes and threads share global address space in WinXP, as they do in Unix?
I would prefer to avoid the overhead of IPC mechanisms. The "overhead" includes my own relearning curve.
The GUI screwed up my indentation. I would try to correct it. But the proper indentation appears when I edit the posting. I suppose I need to insert real tabs. Haven't figured out how (yet).
Not even real tabs work; and I cannot get the "paste as text" button to behave as I expect. What is the trick for posting indented text in this GUI?
#include "stdafx.h" #include <stdlib.h> #include <Windows.h> long curCount; int isRunning; int _tmain(int argc, char* argv[]) { curCount = 0; isRunning = 1;
Understanding Fork() calls. I have to write a C program in UNIX machine, and make two Fork Calls Inside it and have these two instances run every five minutes all round the clock. How to achieve this.
This is in c. Write a program which asks for X numbers, and stores them in an array.
The program then asks the user to enter a number to look for, and tells the user how many times that number appears in the array of numbers (if any), and the array index which contain the number
Make an array of the indexes where the number was found, and then format your output to match my output.
Sample Run:
How many numbers would you like to enter: 5
Please enter a number:1 Please enter a number:2 Please enter a number:3 Please enter a number:4 Please enter a number:2
The numbers you enter were: 1, 2, 3, 4, 2 Please enter a number to find: 2 The number appears 2 times, at array ellements with indexes 1, 4
So we're having an assignment for school where you code a Roulette game which simulates you playing and you can choose how many times you "play" to check how many times you'd win (if that makes any sense, im german :P)
Anyways, the problem is how do i store all the random generated numbers in an array while NOT doing this (it's just a snip):
Code:
void randomzahl(void){ int i; int zahl5[5]; int zahl10[10]; int zahl100[100]; int zahl1000[1000]; int zahl10000[10000]; if(runden == 5)
Write a program which stores 10 decimal numbers in an array. For these numbers accept input from the users. Once the array is populated do the following:
Display each elements of the array Display the sum of all the elements of array
1: Sort Alphabetically 2: Sort Grades Increasing Order (Student) 3: Sort Grades Increasing Order (Project) 4: End Program Enter choice:
Why my sort is not working. Also, I want to keep the same random numbers for the continuation of the program, I don't want new randomized values when I display the table.
I have a program that stores current a low numbers. The Object is to Store the low number every time time one is presented. so say I start the function the first number is the low number. but the trouble im having it once the function is called again it starts over(low number). Is there a way I can keep the function value once the function is called again? Any better way of doing this while keeping function in a class?
double a; class rff{ public: void FGH() { doubleb=0; cout<< "pick a number"<<endl;
Rewriting a program to convert an array based list to a linked list. The program has a user guess a number [1-100] until the correct answer is guessed. I only want to give hints if a duplicate isn't guessed.
while (aGuess-> != p->guess) doesn't work and I haven't been able to troubleshoot myself.
while (aGuess->guess != p->guess) { if ( aGuess->guess > a ) { cout << "That's too high -- try again: "; } // if guess > a
I was working on float and double data types and to see the results i wrote this program:
#include <iostream> #include <iomanip> #include <fstream> using namespace std; int main() { ofstream outputF("output.txt"); double a = 1; double outcome;
[Code] ....
Well I understand the part it cannot store infinite numbers. but if you take a look at the output for example (since it is too long i just added some of the outputs)
//--------------------- for the value of : 001 1 //--------------------- for the value of : 002 0.5 //--------------------- for the value of : 003 0.3333333333333333148
[Code] ....
if you look carefully at the value "5" and "10" results. it is awkwardly abnormal. which is something i couldnt understand. also it is the same with value "20", "25", "40", "50" and so on.
I have to complete a project that i want to read float numbers from keyboard and store them into an array of 10 elements.! Every time that a number stored into array i want to compare with previous one if they have +-10 difference .. I want to keep only 10 elements into my array so every time that i give value a[0] replace a[1], a[1] replace a[2],a[2] replace a[3]. . . .and a[10] deleted.. So when all elements of the array are similar with +-10 values print out the array.!
I am a database developer and I am assigned with a task to finish it as someone left it in the middle.The number 1406357289 ,is a o to 9 pandigital number because it is made up of each of the digits of 0 to 9 in some order,using each digit only once, but it also has a rather interesting sub-string divisibility property. Let d1 be the 1st digit,d2 be the 2nd digit, and so on.In this way,we not the following;
d2d3d4=406 is divisible by 2 d3d4d5=063 is divisible by 3 d4d5d6=635 is divisible by 5 d5d6d7=357 is divisible by 7 d6d7d8=572 is divisible by 11 d7d8d9=728 is divisible by 13 d3d4d5=289 is divisible by 17.
Find the sum of all 0 to 9 pandigital numbers with this property.
This program gets input from a file and output to the screen and to a file. The difficulty I am having is summing the number I retrieve from the file for the individual numbers of sightings.
#include <fstream> // enables us to read and write files #include <iostream> // for cin and cout #include <cstdlib> #include <string> // enables us to hold strings of characters #include <cctype> using namespace std;
I am wondering if there is some repository of c++ code for statistics comparing two columns of numbers? Statistics are so common now that it seems like with the oo concept of reusable code there should be allot of that floating around. Code that would accept two vectors and generate comparisons like pearson's correlation, root mean square error, mean absolute error, median absolute error, etc would be very useful.
I have looked around some and find some code examples, and other posts basically saying, "Google the algorithm and figure it out yourself." At this point, there should almost be stl classes like the ones for union(), intersection(), accumulate(), and other simpler math functions.
I am a beginner and I ALWAYS have the toughest time doing I/O files. It's extremely frustrating. It "seems" it should be so simple. The program should find a code from a list of numbers. These numbers are from 0 - 9, and after each number is a space in the file. Your job is to extract a special code containing only 10 of those numbers. For the number to be part of the code, it should be divisible by 2. After extracting 10 numbers divisible by 2 for the code, write those 10 numbers to the file to form the expected code.
Input file is ("question.txt") Output should be ("code.txt")
Should this contain a "for loop" or If/else ?
Here's what I did . .
/ // int numbers, total, counter; ifstream inFile; inFile.open ("question.txt"); outFile.open ("code.txt"); if (!inFile)
I have been working on the same problem as mp252 from an earlier thread and 4 days later, I appear to have it working. Mine only goes from 0-9999 though as I must move on!
Code: #include <iostream> #include <string> int getThousands(int number); int getHundreds(int number); int getTens(int number); int getUnits(int number); void printNumber(int number);
[Code]......
I had a scrap of paper like a mad scientist trying to find relationships between numbers and the values that they would return through my functions. This is how I arrived at the conditions of my if statements in 'void printNumber'.
I have seen other code that allows a greater range but I can't quite follow it (yet):
I am trying to write code to find all the prime numbers before a user entered number. I started with a working program and when I tried to create a function, it got all messed up.
Code:
#include <stdio.h> int is_prime( int num ); int get_positive_integer(void); int main( ) { int upper; /* upper limit to check */ int num; /* current number to check */ int isprime; /* used to flag if number is prime or not */
im trying to write a source code that find the smallest, largest and average of numbers in array. the code runs fine, but it is not giving the highest number and the the average should include only four number excluding highest and smallest number from the array.
void OlympicJudging() // Olympic Judging { int numbers [6]; double average, sum = 0; int temp; for(int i = 0; i < 6; i++){ cout << "Please type a value for scores: "; cin >> numbers[i];
I wrote a C program that is supposed to create a certain number of child processes, each child process having to change 1 letter from a string. The string and the number of child processes are read from the keyboard. I want to do it using pipes.
It should work like this: The parent changes one letter, then the first child takes the string modified by the parent and changes one more letter. The second child takes the string modified by the first one (2 letters are already changed) and changes one more and so on. I am new to C and am not quite sure how it all works, especially pipes. Also can the children be linked between them through the pipe, or can they only be linked to the parent and it has to be something like: first child changes a letter, gives the string back to the parent and then the second child reads from there, modifies letter and gives back.
If it's like that, is there any way to make sure that this doesn't happen: Apples becomes AppleD and then AppleX and then AppleQ? For example:
Code: Input: Apples Output: Applex Appldx Aqpldx My problem is: I don't get any output from the children.