C++: Arbitrary File Input
 

I can open a file when the filename is hard coded or if I ask the user and store the filename into a string. But I have no idea how to open a file when the filename is only specified at run-time on the command line. For instance:

myProg filename1
myProg filename2
etc.,

myProg needs to input the text from the various files for processing but I don't know how to get at the contents. This isn't redirection either which I would be fine with.

Any ideas?

It's been years since I programmed in C, but isn't this part of the main function? Like, argv() and argc()?

Yup, you need to use the argc and argv parameters to main. argc is the parameter count, and argv is an array of strings that are the command-line parameters tokenized by whitespace.

Thanks... something I hadn't seen before.

I believe array slot 2 has the first command line specified? The first one is the name of the program or something?

Well, technically it's array slot 1, since C/C++/C# use zero-based indexing ;-)

So if argc == 1, there are no arguments, just the name of the program in argv[0].