Spring, 2009
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CSU 380 Lab 1: Introduction
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Purpose:
This is an introductory
lab. Almost all of you will find this easy and trivial , but we want to make
sure everybody knows how to get started. In this lab you will learn
how to write,
compile and run a simple C program.
Lab policy:
You may work in groups
of two students.
You CAN help and speak with other students and other groups.
Tentatively, the check-off of any lab is due at the beginning of
the successive lab (this may change). So if this lab is posted
on a Monday, you must get it checked off
by the following Monday.
How to log in:
In order to log into
a machine you need to have an account. Get
one if you don't have one already. You are provided with two things:
a login (e.g. jcasey) and a secret
password (e.g. mtsh34op
[no, it is not my password]).
Just follow the instruction
on the monitor to log in. You will be required to type your login (in clear)
and then your password (it will not appear on the monitor to prevent people
around you from seeing it). We're not sure how you can read these instructions if you haven't logged in.
Task 0: Log in
Write, compile and
run a simple C program
A C program
is made up of
one or more files. The program we are going to write is really simple.
It will be contained in one simple C file.
Open a console and type
xemacs hello.c &. XEmacs is a program that allow you to edit text files.
You need to know two things:
-
How to save the file
-
How to exit from the program
Press Ctrl + X + C to Save
AND exit
Press Ctrl + X + S to
simply save
This is the code of your
first program (copy it now):
#include <stdio.h>
int main() {
printf("\n\nHello World!!!\n\n");
return 0;
}
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After you have done it
save and close the Xemacs window (Ctrl+ X + C). Now you have written your
first C program. Try to type "ls" to see the list of all the files in your
current directory.
A C program is a text
file. You cannot execute it. You need to compile it and produce an executable
file. In order to do that, type gcc -o hello hello.c. Type "ls" after
the compilation finishes, and you'll see that
the compiler has produced a new file
called hello.
You can execute it now by typing ./hello.
Task 1: Your first
C program
Follow the instructions
of the preceding paragraph and write, compile and execute the "hello world"
program.
Last updated: 1/18/2009