So, you’ve decided to learn C? Well, you made a good choice. This first tutorial is just how to compile a program, and kind of just learn how C works.
Depending on the compiler you want to use, the instructions vary. But, basically you will do the following steps.
For Command-Line compilers on Windows
- Open up Notepad or an equivalent text editor, NOT a word processor or something with fonts.
- Type in the following:
- This is the traditional Hello, World program. Save it as something like “hello.c” ( with the quotes in Notepad).
- Open a command prompt (or a DOS command line)
- Change to the directory that you saved hello.c in (using cd )
- Execute gcc -s hello.c -o hello.exe (For other compilers, look at your manual)
- If you get an error, check your typing and try again.
- Otherwise, type hello and press enter.
- You should get a Hello, World! message. Try going back and changing the message.
When you’re done experimenting, let’s look at what this means:
- #include = Standard Input/Output Header, kind of like a screen “enabler”. This is required for the screen and the keyboard. int main(void) < = The place where the computer starts executing, therefore all statments after this line are executed.
- printf(“Hello, World!\n”); = Prints ‘Hello, World!’ to the screen, as you may have guessed from experimenting.
- return 0; = Return function exit code 0. Kind of advanced, skip for now, until we get to functions.
- > = Braces mark code segments. Notice that the code segment starts at “int main”.
Double quotes (“) mark strings. So, “Hello” is a string, whereas ‘Hello’ is not. (Look-ahead fact: ‘ marks a char constant). “\n” prints a new line to the “console” (screen).
Got that? Good. Now, try to make a program that . . .
- Prints “Hello from C!”
- Then 4 enters
Your solution should look something like this: It’s okay like this, as well: They do the same thing.
C ignores whitespace (Tabs, spaces, enters). So, Will do the same as the first Hello, World! program.