Can I use C++ function _wspawnlp() to call the ssh.exe from my Visual Studio C++ codes?

Question

Hi, experts,
I need to call ssh.exe from VS c++ codes. I tried following from the Visual Studio 2013 c++ codes:
String sExeName("ssh");
String sHost;

    errno_t err = _set_errno(0);
    intptr_t t = _wspawnlp(_P_WAIT, sExeName.c_str(), sExeName.c_str(), sHost.c_str(), NULL);
_get_errno(&err);

ssh.exe is in my path: "%SYSTEMROOT%\System32\OpenSSH". But I always get t = -1, and err = 2, meaning that they cannot find the file. Why is that? What is the correct way to call the ssh.exe?

Thanks,

Answer 1

You can also use ShellExecute

This test works for me, with hardcoded paths for testing (x86 on Windows 10 64) :

BOOL bWow64 = false;
IsWow64Process(GetCurrentProcess(), &bWow64);
if (bWow64)
{
    PVOID OldValue = NULL;
    if (Wow64DisableWow64FsRedirection(&OldValue))
    {
    }
}
HINSTANCE h = ShellExecute(NULL, NULL, L"cmd.exe", L"/c C:\\Windows\\System32\\OpenSSH\\ssh.exe -Q key > c:\\temp\\output.txt", NULL, SW_SHOWNORMAL);

Answer 2

Go to the Configuration Manager and change the platform to x64. The following also got the error code 2 but then changing to x64 fixed it.

const TCHAR* sExeName = _T("C:\\Windows\\System32\\OpenSSH\\ssh.exe");
std::wcout << sExeName << '\n';
errno_t err = _set_errno(0);
intptr_t t = _tspawnlp(_P_WAIT, sExeName, sExeName, NULL);
_get_errno(&err);
std::cout << "Error: " << err << '\n';

There are many variations of spawn so it might be difficult to find answers. Most Windows developers use CreateProcess so searching with that I found Createprocess() of "C:\Windows\System32\OpenSSH\ssh.exe" fails with error=2 - Stack Overflow.

CreateProcess is the Windows API function that a C language spawn would use in Windows.

Answer 3

Using IsWow64Process(GetCurrentProcess(), &bWow64); works for me. I cannot compile 64 bit because of other dependency.

But now I have another question:
I tried to use intptr_t t = _wspawnlp(_P_WAIT, sExeName.c_str(), sExeName.c_str(), sHost.c_str(), NULL); to call ssh.exe to link linux machine. It didn't return the -1, which means that it already found the ssh.exe. But it return 255, and didn't call my function correctly. But if I run from dos prompt, following command works:

ssh xxx@永爱不变 . ~/.zzz.sh