need help with C and a "command line?"

I am using Microsoft Visual Studio C++ 6.0 and I have a simple little code ( "dbl_out") that I can't figure out how to invoke. I can open up a workspace, a .c file, build/compile and run this program and it works, however my problem is... How do I invoke this program using redirection. My book says that it can do it four different ways: dbl_out, dbl_out < infile, dbl_out >utfile, and dbl_out <infile >outfile. What the heck does this mean? Are there other ways to get this program to work besides pressing the execute button in MSVS? Can anyone deliver insight?

Code:

---


#include <stdio.h>

int main (void)
{
        char c;

        while (scanf ("%c", &c) == 1) {
                printf ("%c", c);
                printf ("%c", c);
        }
        return 0;
}

---

>>Are there other ways to get this program to work besides pressing the execute button in MSVS?
Yes, get to a console prompt (DOS prompt), and CD you r way to the directory where you .exe is. Type it's name, and voila, it'll run.

dbl_out Will run the program and wait for you to type something a press enter.

dbl_out < infile Instead of reading input from the keyboard, you program will read infile and process the contents of it.

dbl_out >utfile This is the same as option 1, but with the output redirected to utfile (presumably a typo, meant to be outfile). Output will normally go to the screen.

dbl_out <infile >outfile This is option 2 and 3 combined.