C++ Question (fstream and args)

Sir Carcass

More like arghs. This may be a simple question, but does anyone know why double-clicking the exe of my program creates the output file as expected while dragging files onto it doesn't? Here is my code for reference:

#include <iostream>
#include <string>
#include <fstream>

using namespace std;

int main(int argc, char *argv[])
{
		fstream output, input;
		string h = "this is a test";

		output.open("CombinedList.csv", fstream::out);
		output.write(h.c_str(),h.size());
	
		cout << "press any key...." << endl;
		cin.get();		

		output.close();  

		return 0;
}

I haven't gotten to the meat to this yet because I can't figure out why it's not creating a file when I drag files onto it.

bowen

Huh, I don't see any reason why it wouldn't.

End

it's putting the file the current working directory, which is apparently different if you drag and drop a file onto the executable

Normally it'd be the same directory the program is in, but in the drag and drop case, a little bit of research indicates it would be your home directory (C:\Users\name or C:\Document and Settings\name) instead.

I'm a little curious why you are dragging files onto it if you're not actually looking at your command line, but perhaps that is a yet to be implemented feature for you.

bowen

Well that's a weird behavior.

Sir Carcass

I know the drag and drop functionality is working correctly because I can cause the program to print the paths and file names.

Sir Carcass

End wrote: »

it's putting the file the current working directory, which is apparently different if you drag and drop a file onto the executable

Normally it'd be the same directory the program is in, but in the drag and drop case, a little bit of research indicates it would be your home directory (C:\Users\name or C:\Document and Settings\name) instead.

I'm a little curious why you are dragging files onto it if you're not actually looking at your command line, but perhaps that is a yet to be implemented feature for you.

The ultimate point of this exe is to merge 4 files into 1. The 4 files will be changing each week, so I want to be able to just drag and drop the current 4 onto it. But yeah, I haven't even gotten that far yet.

I just checked, and yep, it's putting it in my users folder. How is that even a good idea.

Is there any way around that?

bowen

Alternatively, put them into a folder and run a batch script like this:

copy/b *.txt merged.txt

Sir Carcass

bowen wrote: »

Alternatively, put them into a folder and run a batch script like this:

copy/b *.txt merged.txt

I also need it to strip out the first line from each file except the first one.

bowen

Ah yes this would get complicated fast then!

bowen

I'd do a ".\\CombinedList.csv" instead. Since I assume you're working on windows that should cheat it.

Sir Carcass

bowen wrote: »

I'd do a ".\\CombinedList.csv" instead. Since I assume you're working on windows that should cheat it.

That doesn't seem to help, unfortunately.

If nothing else, I guess I can hardcode a location, but having it put in the working directory would be so much better.

bowen

Ah yeah now that I think that might not work.

argv[0] should contain a path, but may not be useful. Unfortunately working with a file system is incredibly stupid with C++ at current unless you're using OS specific libraries or Qt/Boost.

End

Yeah, argv[0] would have a path to the executable, but that isn't super reliable (although probably correct enough in this case). The GetModuleFileName() function will also do it, assuming you're on windows.

bowen

Yeah that'd be what I'd use (windows.h should have it)

Though argv[0] can have relative paths. Which might be an issue with the drag and drop.

Rend

I assume you are working in windows? Because this seems like a problem which could be easily handled by a pretty trivial linux bash script.

Sir Carcass

Yeah, this is in XP. I'll research the windows.h thing tomorrow.

Thanks for all of the help so far!