I'm attempting to launch a process from a different process. The mechanism in which this is achieved is not subject to change. Both the launcher and the original process are located in C:\dir.
I'm starting my launcher from a cmd file. The cmd file itself is located somewhere else, and in order for it to find the launcher executable, I'm setting the PATH variable:
set PATH=C:\dir;%PATH%;
launcher.exe
The launcher starts the child process with the following code:
STARTUPINFO startupInfo;
startupInfo.cb = sizeof (STARTUPINFO);
startupInfo.lpReserved = 0;
startupInfo.lpDesktop = NULL;
startupInfo.lpTitle = NULL;
startupInfo.dwX = 0;
startupInfo.dwY = 0;
startupInfo.dwXSize = 0;
startupInfo.dwYSize = 0;
startupInfo.dwXCountChars = 0;
startupInfo.dwYCountChars = 0;
startupInfo.dwFillAttribute = 0;
startupInfo.dwFlags = _showInForeground ? STARTF_USESHOWWINDOW : 0;
startupInfo.wShowWindow = _showInForeground ? 1 : 0;
startupInfo.cbReserved2 = 0;
startupInfo.lpReserved2 = 0;
PROCESS_INFORMATION processInfo;
BOOL retVal = CreateProcess("child.exe", "", NULL, NULL, FALSE,
_showInForeground ? (CREATE_NEW_CONSOLE | CREATE_DEFAULT_ERROR_MODE) : CREATE_DEFAULT_ERROR_MODE,
NULL, NULL, &startupInfo,&processInfo);
It returns 0 and last error is 2, which is File not found.
If it helps, GetCurrentDirectory returns the directory where the cmd is located, not C:\dir. I'm guessing CreateProcess can't find child.exe because PATH is not available to it.
Any ideas how to get this to work?
EDIT: Some good comments with answers (as comments are sometimes overlooked):
Suggestion: set statupInfo.lpDirectory to "c:\dir"
Answer: can't. I'm starting from the cmd because the directory may change.
According to MSDN, CreateProcess actually does search PATH, but only if lpApplicationName is NULL and the executable is the first token in lpCommandLine.
In other words it should work if you call CreateProcess(NULL, "child.exe", ...
I haven't tried it though, so YMMV and so on.
The launcher process can get its own path using GetModuleFileName() that it can use to create the full path to the 2nd executable. There is no need to change the Path environment variable or change the working directoy.
Related
Using C++ (on Windows 10), I'm trying to execute a command in cmd.exe that execute a python file that takes in another file (in csv format).
What I would like to do is the same thing as if I were typing on the command line something like this:
python3 .\plotCSV.py .\filetoplot.csv
Or in better mode:
python3 C:\...\Documents\plotCSV.py C:\...\Documents\filetoplot.csv
For this I'm using ShellExecute like this:
ShellExecute(NULL, "open", "C:\\Windows\\System32\\cmd.exe", "/c \"python3 C:\...\Documents\plotCSV.py C:\...\Documents\filetoplot.csv\"", NULL, SW_SHOWDEFAULT);
And for the csv file selected (filetoplot.csv for example) this works. Except that, for what I need, the name of the csv file is generate and changes every time in my C++ program and is saved in a variable file_name.c_str(). So, if I use this in ShellExecute I have:
ShellExecute(NULL, "open", "C:\\Windows\\System32\\cmd.exe", "/c \"python3 C:\...\Documents\plotCSV.py C:\...\Documents\file_name.c_str()\"", NULL, SW_SHOWDEFAULT);
But unfortunately (obviously) it doesn't work because there really isn't a csv file renamed "file_name.c_str()".
I found also the function ShellExecuteEx and wanting to repeat the same procedure I think the function should be used like this:
SHELLEXECUTEINFO info = {0};
info.cbSize = sizeof(SHELLEXECUTEINFO);
info.fMask = SEE_MASK_NOCLOSEPROCESS;
info.hwnd = NULL;
info.lpVerb = NULL;
info.lpFile = "cmd.exe";
info.lpParameters = ("python3 C:\...\Documents\plotCSV.py C:\...\Documents\file_name.c_str()");
info.lpDirectory = NULL;
info.nShow = SW_SHOW;
info.hInstApp = NULL;
ShellExecuteEx(&info);
But even here it doesn't work (I probably misinterpret how the function works).
Hoping I have explained myself well, I kindly ask for your advice on how to proceed in this regard.
Thank you very much
You are trying to write code inside a string literal.
That is not possible in C++!
You need to first create your dynamic parameter string, then pass it to a function.
std::string has an overloaded + operator that supports string literals (const char *).
std::string param1 = "/c \"python3 C:\\...\\Documents\\plotCSV.py C:\\...\\Documents\\" + file_name + '\"';
ShellExecute(NULL, "open", "C:\\Windows\\System32\\cmd.exe", param1.c_str(), NULL, SW_SHOWDEFAULT);
I'd like to get the name of an application on Windows.
Currently I'm using EnumProcesses() to enumerate all processes and receive a list of PIDs.
Then I'm looping through all PIDs, each iteration looks like this, when aProcess[i] is the current PID:
HANDLE proc = OpenProcess(PROCESS_ALL_ACCESS | PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, false, aProcesses[i]);
std::string processName = get_process_name(proc);
My get_process_name(proc) function uses GetModuleFileNameEx to get the executable path and GetProcessImageFileName in order to retrieve the name of the executable file.
What I want to retrieve is basically the App Name, as it is displayed in the Windows Task Manager.
I've looked throughout Win32 API's documentation and could not find a clue on how to achieve this.
I've tried looking for other ways such as Windows Shell tasklist but it outputs different things, for example- Google Chrome:
Image Name: chrome.exe PID: 84 Session Name: Console
I'd really appreciate any thought on the matter, whether it be the Win32 API or some other way I can implement through C++ code.
You can do this with GetFileVersionInfoA and VerQueryValueA.
You just need to follow the example given in the VerQueryValueA document.
Here is my sample:
struct LANGANDCODEPAGE {
WORD wLanguage;
WORD wCodePage;
} *lpTranslate;
int main()
{
HANDLE handle = OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION , FALSE, 2140); //Modify pid to the pid of your application
if (!handle) return 0;
wchar_t pszFile[MAX_PATH] = L"";
DWORD len = MAX_PATH;
QueryFullProcessImageName(handle, 0, pszFile, &len);
UINT dwBytes, cbTranslate;
DWORD dwSize = GetFileVersionInfoSize(pszFile, (DWORD*)&dwBytes);
if (dwSize == 0) return 0;
LPVOID lpData = (LPVOID)malloc(dwSize);
ZeroMemory(lpData, dwSize);
if (GetFileVersionInfo(pszFile, 0, dwSize, lpData))
{
VerQueryValue(lpData,
L"\\VarFileInfo\\Translation",
(LPVOID*)&lpTranslate,
&cbTranslate);
wchar_t strSubBlock[MAX_PATH] = { 0 };
wchar_t* lpBuffer;
for (int i = 0; i < (cbTranslate / sizeof(struct LANGANDCODEPAGE)); i++)
{
StringCchPrintf(strSubBlock,50,
L"\\StringFileInfo\\%04x%04x\\FileDescription",
lpTranslate[i].wLanguage,
lpTranslate[i].wCodePage);
VerQueryValue(lpData,
strSubBlock,
(void**)&lpBuffer,
&dwBytes);
std::wcout << lpBuffer << std::endl;
}
}
if(lpData) free(lpData);
if (handle) CloseHandle(handle);
return 0;
}
And it works for me:
I think what you want are the "version" resources embedded in the PE file (the executables.)
You seem to be familiar with using Win32 API, so I'm just going to give you some hints.
You have to use LoadLibraryEx to load the EXE file (the Ex suffix is to enable passing the LOAD_LIBRARY_AS_DATAFILE flag,) and then call EnumResourceTypes (also see EnumResourceNames) to enumerate all the resource types/resources in the file, and find what you are looking for and then extract the data with LoadResource. The resource type you want is RT_VERSION.
I'm sure I'm omitting a lot of details (as per usual for Win32 programming,) and there might not be a need for enumeration at all; in which case you may want to call FindResource or FindResourceEx directly (if there is a fixed name for this particular resource.)
As further clarification, this gives you the date you see if you right-click on the EXE file (not the shortcut) in Windows Explorer and select "Properties", then go to the "Details" tab. If that information is indeed what you want (e.g. the "File description" field) then the above method should give you the data.
My code should take arguments, put "+" inbetween them, and search google chrome with this, however I get the error (Command line Argument= "Stack Overflow Site"):
http://www.google.com/search?q=Stack+Overflow+Site'C:\Program' is not
recognized as an internal or external command, operable program or
batch file.
Also in my program I get this error:
error C4996: 'strcpy': This function or variable may be unsafe.
Consider using strcpy_s instead. To disable deprecation, use
_CRT_SECURE_NO_WARNINGS. See online help for details. c:\users\user\documents\visual studio
2013\projects\project1\project1\main.cpp
I have been ignoring this, because I thought it was just a warning, but I'm not sure if it is relevant.
My code:
#include <Windows.h>
#include <string>
#include <iostream>
using namespace std;
int main(int argc, char** argv){
//Loop through arguments and put a "+" between them.
string out = "";
for (int i = 1; i < argc; ++i) {
if (i != 1){
out += "+";
}
out += argv[i];
}
string newout = "C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe \"http://www.google.com/search?q=" + out + "\"";
// set the size of the structures
STARTUPINFO si;
PROCESS_INFORMATION pi;
ZeroMemory(&si, sizeof(si));
si.cb = sizeof(si);
ZeroMemory(&pi, sizeof(pi));
//set y to newout and convert
char *y = new char[newout.length() + 1];
strcpy(y, newout.c_str());
//Run Google Chrome with argument
CreateProcessA("C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe", // the path
y, // 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
);
delete[] y;
cin.ignore();
}
I suspect you are not getting exactly the same error since you
stopped deleting the commandline buffer before using it, but
some different, equally unexpected result.
If you will read the documentation of CreateProcess
you will learn that the parameters:
_In_opt_ LPCTSTR lpApplicationName,
_Inout_opt_ LPTSTR lpCommandLine,
can be supplied in one of three ways, as illustrated:-
Way 1
lpApplicationName = "\path\to\executable"
lpCommandLine = "args for the executable"
which results in a process initiated with the command:
\path\to\executable args for the executable
Way 2
lpApplicationName = NULL
lpCommandLine = "\path\to\executable args for the executable"
which results in the same process as Way 1
Way 3
lpApplicationName = "\path\to\executable"
lpCommandLine = NULL
which results in a process initiated with the command \path\to\executable.
You are not using Way 1 or Way 2 or Way 3, but:
lpApplicationName = "\path\to\executable"
lpCommandLine = "\path\to\executable args for the executable"
which in your case results in a process initiated with the command:
"C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe \
C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe \
http://www.google.com/search?q=Stack+Overflow+Site"
in which the arguments passed to Chrome are:
C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe \
http://www.google.com/search?q=Stack+Overflow+Site"
Of course this does not have the anticipated outcome.
Should you wish to correct this by adopting Way 2, bear particularly
in mind what the documentation says about lpCommandLine:
...
If lpApplicationName is NULL, the first white space–delimited token of the command line specifies the module name.
...
i'm working on a c++ project on windows, and i want to use cygwin not as a target environment, but just as a shell for replacing cmd, my project is actually compiled for windows with mingw.
My program for now just execute a CreateProcess, the problem is that if i call it from the cmd it works, if i execute the program from cygwin it does nothing while still the CreateProcess() is returning true.
That's the code:
int exec_module(const string& name, HANDLE stdIn, HANDLE stdOut, HANDLE stdErr) {
STARTUPINFO child_sinfo = { sizeof(child_sinfo) };
PROCESS_INFORMATION child_pinfo;
ZeroMemory(&child_sinfo, sizeof(child_sinfo));
child_sinfo.cb = sizeof(child_sinfo);
ZeroMemory(&child_pinfo, sizeof(child_pinfo));
child_sinfo.dwFlags = STARTF_USESTDHANDLES;
child_sinfo.hStdInput = stdIn;
child_sinfo.hStdOutput = stdOut;
child_sinfo.hStdError = stdErr;
return CreateProcess(0, _T((char *) name.c_str()), 0, 0, false,0, 0, 0, &child_sinfo, &child_pinfo);
}
And i call it like this:
if (!exec_module("caccone.exe", GetStdHandle(STD_INPUT_HANDLE), GetStdHandle(STD_OUTPUT_HANDLE), GetStdHandle(STD_ERROR_HANDLE))) {
cout << "Errore durante l'esecuzione del modulo" << endl;
}
I just can't figure out what's the problem.
My Bad here, to work well in cygwin i had to add synchronization code between parent and child, but the cmd shell worked also in a naife way.
Thx Harry Johnston for the point on the _T macro.
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.
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.
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!
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.