Lab2

main.cpp

// for getpid, getppid
#include <sys/types.h>
#include <unistd.h>

// for memcpy
#include <string.h>

// for malloc
#include <stdlib.h>

// printf
#include <stdio.h>

// for wait function
#include <sys/wait.h>

#include <iostream>

using namespace std;

int actions();
void act_1();
void act_2();
void act_3();
void act_4();

int act;
char *cmd;

int
main()
{
//    cout << " PID: " << getpid() << endl;
//    cout << "PPID: " << getppid() << endl;

    while(true)
    {
        act = actions();
        switch(act){
            case 1:
                cout << "Run..." << endl;
                act_1();
                break;
            case 2:
                cout << "Executing shell command" << endl;
                act_2();
                break;
            case 3:
                cout << "Forking..." << endl;
                act_3();
                break;
            case 4:
                cout << "Exiting..." << endl;
                act_4();
                break;
        }
    }


}

int
actions()
{
    char *line = NULL;
    size_t line_len = 0;

    cout << "1. Execute enterred command" << endl;
    cout << "2. Run 1'st lab" << endl;
    cout << "3. Execute fork's alghorithm" << endl;
    cout << "4. Exit" << endl;
    cout << "Type action: " ;

    getline(&line, &line_len, stdin);

    return atoi(line);
}

void
act_1()
{
    pid_t p;

    // forking, and save PPID to p variable
    p = fork();
    if (p == 0)
    {
        // critical =) section
        cout << "I'm a CHILD" << endl;

        cout << "Type command: ";
        char *line = NULL;
        size_t line_len = 0;
        getline(&line, &line_len, stdin);

        printf("%s", line);

        system(line);
        printf("Exiting child!\n");
        _exit(0);

    }else
    {
        waitpid(p, 0, 0);
        cout << "I'm PARENT" << endl;
    }
}

void
act_2()
{

}

void
act_3()
{

}

void
act_4()
{
    _exit(0);
}