How can I make a program in c++ that executes another program and receives information from that program on windows?

I was wondering if it was possible to make a program that executes another program, the program that is being executed returns a value that the first program catches, like if they were communicating, an example of this: Program 1 executes Program 2, then Program 2 returns/sends to Program 1 whatever it has to send and then closes

Is this possible in c/c++ ?

The simplest approach is to use pipes (i.e. popen, pclose). Here is a detailed example. The following code provides a simple example.

Sample Code

#include <stdio.h>
#include <iostream>

int main(int argc, const char *argv[]) {
    FILE *pipe = popen("ls", "r");

    char c;
    while ((c = fgetc(pipe)) != EOF)
        putchar(c);

    pclose(pipe);

    return 0;
}

Output

CMakeCache.txt
CMakeFiles
CPackConfig.cmake
CPackSourceConfig.cmake
Makefile
...

You may also want to look at this answer.

Every execution of a program happens inside a process. Your code can spawn another process, which will become its child process, and can wait on it to complete execution and get back the return value. I would suggest reading more on processes. How you achieve this is using the fork() system call. It makes two copies of the process and returns different values in both copies so you can distinguish which process is which. It returns 0 in the child process and process id of the child process in the parent process. Then in the child process you can use one of the system calls from the exec family like execlp(all the functions in exec family differ in the arguments you provide to them, I would suggest reading manpages) to execute your second program. In the parent process, you can wait on the child process to finish execution using the wait() system call and then get back it's return value in a variable. The below code snippet should be helpful

#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

int main() {
    pid_t childPid = fork();

if (childPid == -1) {
    // Handle fork error
} else if (childPid == 0) {
    // Code for the child process
    execlp("program", "program", arg1, arg2, ..., (char*) NULL);
    //Program here is the path to the program you want to run
} else {
    // Code for the parent process
    int status;
    wait(&status);
    if (WIFEXITED(status)) {
        int returnValue = WEXITSTATUS(status);
        // Use the returnValue as needed
    } else {
        // Child process exited abnormally
    }
}

return 0;

}