How do you run external programs with parameters without the cmd window showing up in Windows? - c++

Question

I just asked a question earlier today because I wanted to run an executable file that takes parameters from my C++ code and it wasn't working.
It works now, but I'm still having problems since I thought I was going the right way about this, but it seems like what I want to accomplish can't be done the way I'm approaching it...
This is my corrected code from my other question:
#include <stdlib.h>
#include <conio.h>
int main (){
system("\"\"C:\\Users\\Adam\\Desktop\\pdftotext\" -layout \"C:\\Users\\Adam\\Desktop\\week 4.pdf\"\"");
_getch();
}
which is me running "pdftotext -layout myfile.pdf" as if I was running it from a CMD window.
The thing is, I don't actually want the cmd to show up since I have a GUI interface on top of it and I want to display a nicer progress bar instead of seeing the windows pop-up for every file I need to parse.
I looked around and either I don't understand what I'm reading since I'm relatively new to C++, or I just didn't find what I was looking for. I found that using CreateProcess, I should be able to do this, but after copying some code I found somewhere else, the cmd window pops-up anyway.
I'd like it if someone could give me the name of a function I could use to accomplish something like this or if someone could give some example code for this small case in the code I posted since I'm not sure I understand everything as I should, being new to C++ and all.
Edit: As requested in a comment, the code for CreateProcess that I tried is what I found at this url:
http://www.goffconcepts.com/techarticles/development/cpp/createprocess.html
Which is (with my own parameters that I think should go there):
#include <windows.h>
#include <string>
#include <conio.h>
size_t ExecuteProcess(std::wstring FullPathToExe, std::wstring Parameters, size_t SecondsToWait)
{
size_t iMyCounter = 0, iReturnVal = 0, iPos = 0;
DWORD dwExitCode = 0;
std::wstring sTempStr = L"";
/* - NOTE - You should check here to see if the exe even exists */
/* Add a space to the beginning of the Parameters */
if (Parameters.size() != 0)
{
if (Parameters[0] != L' ')
{
Parameters.insert(0,L" ");
}
}
/* The first parameter needs to be the exe itself */
sTempStr = FullPathToExe;
iPos = sTempStr.find_last_of(L"\\");
sTempStr.erase(0, iPos +1);
Parameters = sTempStr.append(Parameters);
/* CreateProcessW can modify Parameters thus we allocate needed memory */
wchar_t * pwszParam = new wchar_t[Parameters.size() + 1];
if (pwszParam == 0)
{
return 1;
}
const wchar_t* pchrTemp = Parameters.c_str();
wcscpy_s(pwszParam, Parameters.size() + 1, pchrTemp);
/* CreateProcess API initialization */
STARTUPINFOW siStartupInfo;
PROCESS_INFORMATION piProcessInfo;
memset(&siStartupInfo, 0, sizeof(siStartupInfo));
memset(&piProcessInfo, 0, sizeof(piProcessInfo));
siStartupInfo.cb = sizeof(siStartupInfo);
if (CreateProcessW(const_cast<LPCWSTR>(FullPathToExe.c_str()),
pwszParam, 0, 0, false,
CREATE_DEFAULT_ERROR_MODE, 0, 0,
&siStartupInfo, &piProcessInfo) != false)
{
/* Watch the process. */
dwExitCode = WaitForSingleObject(piProcessInfo.hProcess, (SecondsToWait * 1000));
}
else
{
/* CreateProcess failed */
iReturnVal = GetLastError();
}
/* Free memory */
delete[]pwszParam;
pwszParam = 0;
/* Release handles */
CloseHandle(piProcessInfo.hProcess);
CloseHandle(piProcessInfo.hThread);
return iReturnVal;
}
int main(void){
ExecuteProcess(L"C:\\Users\\Adam\\Desktop\\pdftotext", L"-layout \"C:\\Users\\Adam\\Desktop\\week 4.pdf\"", 0);
_getch();
}
I'm a little bit overwhelmed since it uses some things I've never used before, but I think I understand the core (keyword: think). It doesn't solve my problem, though, because the cmd shows up and by retesting it I actually noticed that the cmd doesn't even run the .exe and doesn't give me an error message.
I hope this bit of code helps... I didn't want to look into it further since it seemed like I wasn't even going in the right direction.

Answer 1

Use CreateProcess instead of system.
--EDIT--
the code for CreateProcess that I tried is what I found at this url:
The code is a mess, I'd advise to avoid that url in future.
At the end of "CreateProcess" article is a link named "Creating Processes", which contains simpler example that is easier to read. Use it as a starting point.

Answer 2

After adding the following lines for siStartupInfo, cmd window won't pop up any more with my own test *.exe.
siStartupInfo.dwFlags = STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW;
siStartupInfo.hStdInput = GetStdHandle(STD_INPUT_HANDLE);
siStartupInfo.hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);
siStartupInfo.hStdError = GetStdHandle(STD_ERROR_HANDLE);
siStartupInfo.wShowWindow = SW_HIDE;
But I have another problem. As I try to run some other executable, whose command line would be
TEST.exe <input-file> output-file
in a cmd window, WaitForSingleObject() return 258, and GetLastError() return 1813 ("The specified resource type cannot be found in the image file.").
See system() and CreateProcess() / CreateProcessW() for more details.
Any ideas would be highly appreciated!

Answer 3

The only way I found how to execute an external program is:
system("start C:\file path\ file");
The only problem is that the file or directory can't have spaces.