C++ Execute a command line and get Result. - c++

Question

I need some help with my situation. I want to execute a Terminal and get the Result. I have done it so far, but i want to do some other Commands after getting the Result. My Problem is, that everytime when i do a command, the console restarts, and i dont know how to write in a active prozess.
I have done it like that:
FILE *fp = popen(r.c_str(),"r");
char buf[2560];
while (fgets(buf, 2560, fp))
{
s->SendLine(buf);
}
fclose(fp);
I want to "send" another command in the same process. How can i do that?

Answer 1

Assuming I understood your question and comment. It sounds like you want your program to run in a loop until the user chooses to close it. You will want something like this:
bool keepProgramOpen = true;
public void main()
{
while(keepProgramOpen)
{
printf("Choose and option\n");
printf("Option 1: press 1\n");
printf("Option 2: press 2\n"); //etc
char result = getchar();
switch result
{
//code to select which option was picked
case 1:
fileFunction();
break;
case 2:
someOtherFunction();
break;
case 3:
closeProgram(); //set keepProgramOpen false in here to end program
break;
//etc
}
}
}
fileFunction()
{
FILE *fp = popen(r.c_str(),"r");
char buf[2560];
while (fgets(buf, 2560, fp))
{
s->SendLine(buf);
}
fclose(fp);
}

Answer 2

I think before fclose(fp) use r2 as
fputs(r2.c_str(),fp)