Originally posted by Draco
I put the program into the command line like WaltP said...it opened up the program and created a file for the output, but nothing I did on the keyboard would register as input, not even CTRL+C to force it to close.
As Hammer said, you need to be specific.

I put the program which program? into the command line like WaltP said...it opened up the program which program? and created a file for the output, but nothing I did on the keyboard would register as input, not even CTRL+C to force it to close. what is supposed to accept keyboard input?

It helps to tell us what the program before the pipe is supposed to do, and how that is interacting with the filter program....

***Lightbulb***
The program you are trying to run accepts keyboard input -- this is possibly the problem. When you pipe information, all the input is buffered and sent to the filter program in chunks. Therefore you can't write prompts to stdio. Output everything that must go to the screen to stderr with fprintf()