Source Code, Compiling, and Executable Code
C is a highly robust and flexible programming language that is very
useful for scientific programs. Before a program can be executed
by a computer, it must undergo a transformation from a human-readable format
to something that can be understood by the computer. The source
code is the C program that is written by a human using a text editor,
such as vi. An example of a source code in C is given here.
This code is easily written and read by humans and can be translated into
a code that can be executed by a computer. Source code is converted
to executable code (which is useful to the computer) by a process
called compiling. All source code in C usually has a ".c"
suffix appended to the filename, as in the case of hello_world.c
file, to indicate that the source code is written in C. The source
code can be transformed into executable code by using the GNU C compiler
(gcc). The executable or machine code produced is named whatever
you wish using the "-o" flag of the gcc compiler. For convenience,
the execuatable is usually named the same name as the source code (without
the ".c" suffix). The executable code can then be run on the machine
by typing ./ (to tell the shell
that the program is located in the current directory) followed by the name
of the executable code.
Make sure that the gcc compiler is set up to work with your computer account.
Add the command use -quiet comp to your .aliases file.
Resource .cshrc by typing source .cshrc
Check to see if gcc exists by typing which
Compile the source code.
gcc -o hello_world hello_world.c