Here's a command to compile in Unix:
gcc -o executable file1.c file2.c ... #This is for C. For C++, the command is not gcc but g++.
This compiles file1.c, file2.c, etc., and creates an executable named "executable."
gcc -c file1.c
This compiles file1.c and gives you file1.o, the object code to be linked later:
gcc -o executable file1.o file2.c ...
With lex (unless yacc is involved too), you'll need to add -ll to the end:
gcc -o executable lex.yy.c -ll
To run, type this:
./executable
Easiest way for me: create a subfolder and copy everything into it:
mkdir old
cp * old
Note that if you make a typo, it won't catch it. This code copies all files to a new file named "olf," which is not what you wanted:
mkdir old
cp * olf
To back up to another machine -- and you should -- use Dropbox.
A Makefile, which is named "Makefile" and resides in the directory with your code, tells Unix how to compile your program -- like a Visual Studio project file.
To run it, type make.
Here's a tutorial. I think you can use Makefile1 or Makefile4. I have never used the -I option.