Question

I am now using Visual C++ 2010 to open a txt file.

fp = fopen("E:\\CProg\\Huffman\\Debug\\Huffman.txt","r"); //Right
//Wrong
//fp = fopen(".\\Huffman.txt","r");
//fp = fopen("\\Huffman.txt","r");
//fp = fopen("Huffman.txt","r");

In VB.NET, I used to write like this: Application.Startpath & “\”. Then how do I make it in C?

Answer 1

Relative to what? On “all relevant platforms”, if you use a filename that’s not absolute it will be resolved relative to the current directory.

The following is for Windows.

If you are writing a console application, the application will start with the current directory set to whatever the command prompt shows. Without further research I can’t tell what the initial current directory for a GUI application will be.

If you want your filename to be relative to the Installation directory you’ll have to use something like the Win32 function GetModuleFileNameW() and work your way from there (the function gives you the pathname to the exe file; remove the last component to get the directory, and append whatever path you want to append)-

There is no direct way to say “I want this filename to be used relative to the installation directory”.