Now we've talked about everything in joints.c'' except for what?
Click here for the answer.
A program that neither asks for input nor prints out its answers isn't very
useful, so we'd better talk about these things now.
Most programs need to communicate with something outside themselves--something
in the ``outside world'' like a human being or a data file or a printer--in
order to be useful. The process of reading data from that outside world is
called input, and the process of sending messages to the outside world is
called output. These two concepts are often grouped together and
abbreviated as ``I/O'' which stands for ``input/output.''
Communicating with the outside world can be a very complicated task for a
program. It can require a lot of programmer effort to get the output from a
program to look just right or to handle all of the various problems that might
arise. For example, a program that sends output to a printer might want to do
something special when the printer runs out of paper.
We don't have the time (or the need) to teach you every detail about how C
programs can do I/O. Instead, these lessons will just stick to the basics.
Eric N. Eide
Hamlet Project
Department of Computer Science
University of Utah