c++ how to write to a process that was created with createProcess - c++

Question

I am creating a new Powershell process via createProcess and would like to write a command to that Powershell window and hit Enter. Here is what I have:
#include <cstdio>
#include <windows.h>
#include <tlhelp32.h>
#include <string>
#include <iostream>
using namespace std;
int main(int argc, char *argv[])
{
STARTUPINFO si;
PROCESS_INFORMATION pi;
ZeroMemory(&si, sizeof(si));
si.cb = sizeof(si);
ZeroMemory(&pi, sizeof(pi));
char myCommand[] = "cmd /c powershell.exe -NoExit";
CreateProcess(NULL, // No module name (use command line)
myCommand, // Command line
NULL, // Process handle not inheritable
NULL, // Thread handle not inheritable
FALSE, // Set handle inheritance to FALSE
0, // No creation flags
NULL, // Use parent's environment block
NULL, // Use parent's starting directory
&si, // Pointer to STARTUPINFO structure
&pi); // Pointer to PROCESS_INFORMATION structure
Sleep(5000);
string strMytestString("ls");
cout << strMytestString.c_str();
Sleep(2000);
// ENTER key down
keybd_event(VK_RETURN, 0x9C, 0, 0);
// ENTER key up
keybd_event(VK_RETURN, 0x9C, KEYEVENTF_KEYUP, 0);
return 0;
}
It opens the powershell and writes "ls" into it and hits Enter but Powershell does not take it as a command and does not do the "ls" but write it as a normal text.
Is there a way to make Powershell execute that command that I pass to it as a String?

Answer 1

Try to read a little bit more about STDIN, STDOUT and STDERR.
To achieve your intention, you have to pass commands into STDIN of child process.
Take a look for MSDN post Creating a Child Process with Redirected Input and Output that shown exactly what you need.