[c++] How to get Current Directory?

I've been doing this in C# and Delphi ,but C++ is evil.The purpose is to create a file in the current directory(where the executable is running).

My code:

LPTSTR NPath = NULL;
DWORD a = GetCurrentDirectory(MAX_PATH,NPath);
HANDLE hNewFile = CreateFile(NPath,GENERIC_WRITE,0,NULL,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);

I get exception at GetCurrentDirectory().

Please tell me why I get an exception and how do I make it easier in C++?

An easy way to do this is:

int main(int argc, char * argv[]){
    std::cout << argv[0]; 
    std::cin.get();
}

argv[] is pretty much an array containing arguments you ran the .exe with, but the first one is always a path to the executable. If I build this the console shows: C:\Users\Ulisse\source\repos\altcmd\Debug\currentdir.exe

The question is not clear whether the current working directory is wanted or the path of the directory containing the executable.

Most answers seem to answer the latter.

But for the former, and for the second part of the question of creating the file, the C++17 standard now incorporates the filesystem library which simplifies this a lot:

#include <filesystem>
#include <iostream>

std::filesystem::path cwd = std::filesystem::current_path() / "filename.txt";
std::ofstream file(cwd.string());
file.close();

This fetches the current working directory, adds the filename to the path and creates an empty file. Note that the path object takes care of os dependent path handling, so cwd.string() returns an os dependent path string. Neato.

GetCurrentDirectory() gets the current directory which is where the exe is invoked from. To get the location of the exe, use GetModuleFileName(NULL ...). if you have the handle to the exe, or you can derive it from GetCommandLine() if you don't.

As Mr. Butterworth points out, you don't need a handle.

#include <windows.h>
using namespace std;

// The directory path returned by native GetCurrentDirectory() no end backslash
string getCurrentDirectoryOnWindows()
{
    const unsigned long maxDir = 260;
    char currentDir[maxDir];
    GetCurrentDirectory(maxDir, currentDir);
    return string(currentDir);
}

To find the directory where your executable is, you can use:

TCHAR szFilePath[_MAX_PATH];
::GetModuleFileName(NULL, szFilePath, _MAX_PATH);

String^ exePath = Application::ExecutablePath;<br>
MessageBox::Show(exePath);

Code snippets from my CAE project with unicode development environment:

/// @brief Gets current module file path. 
std::string getModuleFilePath() {
    TCHAR buffer[MAX_PATH];
    GetModuleFileName( NULL, buffer, MAX_PATH );
    CT2CA pszPath(buffer);
    std::string path(pszPath);
    std::string::size_type pos = path.find_last_of("\\/");
    return path.substr( 0, pos);
}

Just use the templete CA2CAEX or CA2AEX which calls the internal API ::MultiByteToWideChar or ::WideCharToMultiByte?

Why does nobody here consider using this simple code?

TCHAR szDir[MAX_PATH] = { 0 };

GetModuleFileName(NULL, szDir, MAX_PATH);
szDir[std::string(szDir).find_last_of("\\/")] = 0;

or even simpler

TCHAR szDir[MAX_PATH] = { 0 };
TCHAR* szEnd = nullptr;
GetModuleFileName(NULL, szDir, MAX_PATH);
szEnd = _tcsrchr(szDir, '\\');
*szEnd = 0;

WCHAR path[MAX_PATH] = {0};
GetModuleFileName(NULL, path, MAX_PATH);
PathRemoveFileSpec(path);

You should provide a valid buffer placeholder. that is:

TCHAR s[100];
DWORD a = GetCurrentDirectory(100, s);

GetCurrentDirectory does not allocate space for the result, it's up to you to do that.

TCHAR NPath[MAX_PATH];
GetCurrentDirectory(MAX_PATH, NPath);

Also, take a look at Boost.Filesystem library if you want to do this the C++ way.

You can remove the filename from GetModuleFileName() with more elegant way:

TCHAR fullPath[MAX_PATH];
TCHAR driveLetter[3];
TCHAR directory[MAX_PATH];
TCHAR FinalPath[MAX_PATH];
GetModuleFileName(NULL, fullPath, MAX_PATH);
_splitpath(fullPath, driveLetter, directory, NULL, NULL);
sprintf(FinalPath, "%s%s",driveLetter, directory);

Hope it helps!

IMHO here are some improvements to anon's answer.

#include <windows.h>
#include <string>
#include <iostream>

std::string GetExeFileName()
{
  char buffer[MAX_PATH];
  GetModuleFileName( NULL, buffer, MAX_PATH );
  return std::string(buffer);
}

std::string GetExePath() 
{
  std::string f = GetExeFileName();
  return f.substr(0, f.find_last_of( "\\/" ));
}

Please don't forget to initialize your buffers to something before utilizing them. And just as important, give your string buffers space for the ending null

TCHAR path[MAX_PATH+1] = L"";
DWORD len = GetCurrentDirectory(MAX_PATH, path);

Reference

#include <iostream>    
#include <stdio.h>
#include <dirent.h>

std::string current_working_directory()
{
    char* cwd = _getcwd( 0, 0 ) ; // **** microsoft specific ****
    std::string working_directory(cwd) ;
    std::free(cwd) ;
    return working_directory ;
}

int main(){
    std::cout << "i am now in " << current_working_directory() << endl;
}

I failed to use GetModuleFileName correctly. I found this work very well. just tested on Windows, not yet try on Linux :)

If you are using the Poco library, it's a one liner and it should work on all platforms I think.

Poco::Path::current()

I guess, that the easiest way to locate the current directory is to cut it from command line args.

#include <string>
#include <iostream>

int main(int argc, char* argv[])
{
  std::string cur_dir(argv[0]);
  int pos = cur_dir.find_last_of("/\\");

  std::cout << "path: " << cur_dir.substr(0, pos) << std::endl;
  std::cout << "file: " << cur_dir.substr(pos+1) << std::endl;
  return 0;
}

You may know that every program gets its executable name as first command line argument. So you can use this.