如何使用C ++以编程方式杀死进程？

Question

Guys i am trying to kill the process through the C++ program , it's killing the process, but not getting the desired output after killing the process, my desired output is to display the remaining running processes after killing the process which is in if block ,instead of that it is displaying the else block. I inter changed if block & else block too still not getting the desired output. Here is the code:

#include<iostream>
#include<cstdlib>
#include<csignal>
using namespace std;
int main()
{   
    int pid,f=0;
    system("ps -all");
    cout<<"Enter the Process ID to kill\n";
    cin>>pid;
    if((kill(pid,SIGKILL))){
        f=1;
    }
    if(f)
    {
        cout<<"List of processes after killing the process with PID"<<pid<<"are"<<"\n";
        system("ps -l");
    }
    else    
    {   
        cout<<"Cant kill the process\n";
    }   
    return 0;
}

Answer 1

You need to switch your if/else cases: kill() returns 0 when it succeeds, and -1 when it fails. You're setting f=1 only when it fails.

Also, when it fails, it sets errno to an error code that provides a reason for the failure. You can use a function like perror() or strerror() to get a descriptive error message based on that error code.