In this lab, you will learn how to use the cygwin/gcc environment to write, compile, and run C programs.
Getting Started
(1) Note that the first step will be slightly different, depending on whether you are using Linux (KEC 119) or Windows (any other KEC lab).
Windows
Start the cygwin bash shell. This is available from the Start menu on all of the computers in the KEC building. The full path in the menu is:
Start → All Programs → Cygwin → Cygwin Terminal
Once the cygwin bash shell has started, type the following commands, pressing the Enter key after each command:
cd h:
mkdir -p CS101
cd CS101
Linux
Start a terminal by opening the Mint menu and choosing System Tools → Terminal.
In the terminal, run the commands:
mkdir -p CS101
cd CS101
(2) Using a web browser, download CS101_Lab01.zip. Save the zip file in the CS101 directory within your home directory.
(3) From the Cygwin bash shell or terminal, run the following command:
unzip CS101_Lab01.zip
When you run this command, you should see output looking something like the following:
Archive: CS101_Lab01.zip
extracting: CS101_Lab01/hello.cpp
inflating: CS101_Lab01/Makefile
inflating: CS101_Lab01/submitToMarmoset.pl
(4) Navigate into the CS101_Lab01 directory containing the lab files:
cd CS101_Lab01
(5) Start the Notepad++ (Windows) or Pluma (Linux) text editor.
On Windows, Notepad++ is available from the Start menu:
Start → All Programs → Notepad++ → Notepad++
On Linux, Pluma is available by opening the Mint menu and choosing Accessories → Text editor.
Once your text editor has started, choose File→Open from the menu, and open the file
CS101_Lab01/hello.cpp
Your Task
Your task is to add a main function to the hello.cpp file to accomplish the following tasks:
- Print the message Hello, CS 101! to the output window
- Prompt the user for their age in years. Store the value entered by the user in an int variable.
- Print the message OK, you are N years old, where N is the integer value entered by the user.
Here is an example run (user input in bold):
Hello, CS 101! How old are you? 36 OK, you are 36 years old
To compile the program (run the compiler to translate your C source code into an executable file), run the following command using the Cygwin bash shell:
make
If the compilation is successful, you should see something like the following output:
g++ -g -Wall -c -o hello.o hello.cpp
g++ -o hello.exe hello.o
If you see a compiler error message, ask the instructor or lab coach for help.
Once the program is compiled, run the program by typing the following command in the Cygwin bash shell:
./hello.exe
Hints
- Put #include <stdio.h> at the top of hello.cpp. This will allow your progam to use the printf and scanf functions.
- Use the printf function to print output to the screen.
- Declare an int variable to store the user’s age.
- Use the scanf function to read the user’s age.
Submitting
When you are done, run the following command from the Cygwin bash shell:
make submit
You will be prompted for your Marmoset username and password, which you should have received by email. The entire submission process should produce output that looks something like the following:
You will use your own username in place of “jstudent”. Note that when you type your password, it will not be echoed to the screen.
Important:
You must submit your work before leaving class. If you do not submit, you will not receive any credit for the lab.