There is an example of how to call CreateProcess on stack exchange here, however this seems to be no longer supported on Windows 10, and you must use the unicode version CreateProcessW.
In a similar vein to the ASCI version, I am looking for an example that:
There is nothing new about Windows 10 in this respect. Your question is really about Unicode versus ANSI, and Visual Studio's new default settings which use Unicode.
CreateProcess is a macro, it is defined as
#ifdef UNICODE
#define CreateProcess CreateProcessW
#else
#define CreateProcess CreateProcessA
#endif // !UNICODE
In addition STARTUPINFO is a macro for STARTUPINFOA and STARTUPINFOW
CreateProcessA uses ANSI char strings char* and STARTUPINFOA
CreateProcessW uses Unicode wide char strings wchar_t* and STARTUPINFOW
If you insist on using ANSI (not recommended) then go to Project Settings -> Character Set and disable Unicode.
If you insist on using ANSI version with Unicode settings (still not recommended), you need
//Using ANSI when UNICODE is defined (not recommended):
STARTUPINFOA si = { sizeof(si) };
PROCESS_INFORMATION pi;
std::string path = "c:\\windows\\notepad.exe \"c:\\test\\_text.txt\"";
//if not using C++11 or later, force a zero at the end
//to make sure path is null-ternminated
path.push_back(0);
if(CreateProcessA(NULL, &path[0], NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi))
{
WaitForSingleObject(pi.hProcess, INFINITE);
CloseHandle(pi.hProcess);
CloseHandle(pi.hThread);
}
Above code will work as long as the directory names are ANSI compatible. But the recommended version is:
//recommended:
{
STARTUPINFO si = { sizeof(si) };
PROCESS_INFORMATION pi;
std::wstring path = L"c:\\windows\\notepad.exe \"c:\\test\\_text.txt\"";
//if not using C++11 or later, force a zero at the end
//to make sure path is null-ternminated
path.push_back(0);
if(CreateProcess(0, &path[0], NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi))
{
WaitForSingleObject(pi.hProcess, INFINITE);
CloseHandle(pi.hProcess);
CloseHandle(pi.hThread);
}
}
Also, don't cast from constant string to string as follows:
wchar_t* arg_concat = const_cast<wchar_t*>( input.c_str() );
The second argument in CreateProcess should be wchar_t* because the process may modify the command line.
This example is commented and hopefully self explanatory.
#ifdef _WIN32
#include <windows.h>
#include <stdio.h>
#include <tchar.h>
#include <cstdlib>
#include <string>
#include <algorithm>
class process
{
public:
static PROCESS_INFORMATION launchProcess(std::string app, std::string arg)
{
// Prepare handles.
STARTUPINFO si;
PROCESS_INFORMATION pi; // The function returns this
ZeroMemory( &si, sizeof(si) );
si.cb = sizeof(si);
ZeroMemory( &pi, sizeof(pi) );
//Prepare CreateProcess args
std::wstring app_w(app.length(), L' '); // Make room for characters
std::copy(app.begin(), app.end(), app_w.begin()); // Copy string to wstring.
std::wstring arg_w(arg.length(), L' '); // Make room for characters
std::copy(arg.begin(), arg.end(), arg_w.begin()); // Copy string to wstring.
std::wstring input = app_w + L" " + arg_w;
wchar_t* arg_concat = const_cast<wchar_t*>( input.c_str() );
const wchar_t* app_const = app_w.c_str();
// Start the child process.
if( !CreateProcessW(
app_const, // app path
arg_concat, // Command line (needs to include app path as first argument. args seperated by whitepace)
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
)
{
printf( "CreateProcess failed (%d).\n", GetLastError() );
throw std::exception("Could not create child process");
}
else
{
// Return process handle
return pi;
}
}
static bool checkIfProcessIsActive(PROCESS_INFORMATION pi)
{
// Check if handle is closed
if ( pi.hProcess == NULL )
{
printf( "Process handle is closed or invalid (%d).\n");
return FALSE;
}
// If handle open, check if process is active
DWORD lpExitCode = 0;
if( GetExitCodeProcess(pi.hProcess, &lpExitCode) == 0)
{
printf( "Cannot return exit code (%d).\n", GetLastError() );
throw std::exception("Cannot return exit code");
}
else
{
if (lpExitCode == STILL_ACTIVE)
{
return TRUE;
}
else
{
return FALSE;
}
}
}
static bool stopProcess( PROCESS_INFORMATION &pi)
{
// Check if handle is invalid or has allready been closed
if ( pi.hProcess == NULL )
{
printf( "Process handle invalid. Possibly allready been closed (%d).\n");
return 0;
}
// Terminate Process
if( !TerminateProcess(pi.hProcess,1))
{
printf( "ExitProcess failed (%d).\n", GetLastError() );
return 0;
}
// Wait until child process exits.
if( WaitForSingleObject( pi.hProcess, INFINITE ) == WAIT_FAILED)
{
printf( "Wait for exit process failed(%d).\n", GetLastError() );
return 0;
}
// Close process and thread handles.
if( !CloseHandle( pi.hProcess ))
{
printf( "Cannot close process handle(%d).\n", GetLastError() );
return 0;
}
else
{
pi.hProcess = NULL;
}
if( !CloseHandle( pi.hThread ))
{
printf( "Cannot close thread handle (%d).\n", GetLastError() );
return 0;
}
else
{
pi.hProcess = NULL;
}
return 1;
}
};//class process
#endif //win32