How to trim the space from the lpApplicationName of the CreateProcessW function? - c++

Question

I am using CreateProcessW function to create a process. Into this function, passing the first parameter i.e., lpApplicationName with some spaces like as shown below:
In the below path (pszExePath) there are spaces because of this process is not creating.
pszExePath = L"C:\\Program Files\\Common Files\\Installer\\emrinst.exe";
I tried to trim the space by using the below lines but still i am facing the issue.
pszExePath = L"\"";
pszExePath += L"C:\\Program Files\\Common Files\\Installer\\emrinst.exe";
pszExePath += L"\"";
How to trim the space from the lpApplicationName of the CreateProcessW function?
Below is the updated code:
pszExePath = L"C:\\Program Files\\Common Files\\Installer\\emrinst.exe";
strCommandLine = "C:\\Testfolder\\Program Files\\Common Files\\Apps\\emarmain\\emr-test_folder\\Millinnium Files\\test\\test.inf";
std::wstring strFullPath = L"";
strFullPath += pszExePath;
strFullPath += pszCmdLine;
dwExitCode = ::CreateProcessW(NULL, (LPWSTR)strFullPath.c_str(),
0, 0, FALSE, NORMAL_PRIORITY_CLASS, 0,
pszCurrentDirectory, &si, &pi);
still I am getting the error, I think it is exceeding the size of the second parameter "lpCommandLine" of 32,768 characters. Is there any way to increase the size? And also is my code snippet is correct?

Answer 1

As you have no doubt read in the documentation:
If you are using a long file name that contains a space, use quoted strings to indicate where the file name ends and the arguments begin; otherwise, the file name is ambiguous.
So you've got that part right, but you can't concatenate C strings like that. Instead, you can do:
#include <string>
std::wstring cmdline = L"\"";
cmdline += L"C:\\Program Files\\Common Files\\Installer\\emrinst.exe";
cmdline += L"\"";
CreateProcess (NULL, &cmdline [0], ...);
Alternatively, you can pass the application path as yhe first parameter of CreateProcess without quotes.

Answer 2

Following the MSDN documentation for CreateProcess (Unicode) and the code in the question:
1) Add double quotes to the EXE path and the command line.
2) Add whitespace between the pszExePath and strCommandLine.
3) Note: This solution requires a C++11 since CreateProcess requires a non-read only string as lpCommandLine parameter. For prior versions of C++, use _wcsdup to duplicate the string and call for free to release it.
std::wstring pszExePath = L"C:\\Program Files\\Common Files\\Installer\\emrinst.exe";
std::wstring strCommandLine = L"C:\\Testfolder\\Program Files\\Common Files\\Apps\\emarmain\\emr-test_folder\\Millinnium Files\\test\\test.inf";
std::wstring strFullPath = L"\"" + pszExePath + L"\"" + L" " + L"\"" + strCommandLine + L"\"";
PROCESS_INFORMATION pi;
STARTUPINFO si;
ZeroMemory(&si, sizeof(si));
si.cb = sizeof si;
BOOL result = ::CreateProcessW(NULL, &strFullPath[0], 0, 0, FALSE, NORMAL_PRIORITY_CLASS, 0, pszCurrentDirectory, &si, &pi);
if (result)
{
CloseHandle(pi.hThread);
CloseHandle(pi.hProcess);
}
Edit:
Alternatively, you could try ShellExecuteW (pay attention to double quotes in both paths).
std::wstring pszExePath = L"\"C:\\Program Files\\Common Files\\Installer\\emrinst.exe\"";
std::wstring strCommandLine = L"\"C:\\Testfolder\\Program Files\\Common Files\\Apps\\emarmain\\emr-test_folder\\Millinnium Files\\test\\test.inf\"";
ShellExecute(0, L"open", pszExePath.c_str(), strCommandLine.c_str(), pszCurrentDirectory, SW_NORMAL);