# Descent into C

 1. Hopefully, you remember how to use the shell and how to browse
    these documents from last week. If you need to review, just run:
    
        $ cat ~/pb152/00/intro.txt
    
    The lecture for today, however, starts here:
    
        $ cd ~/pb152/02
        $ cat intro.txt

 2. Today, we will get acquainted with the C compiler, the linker
    and we will write some very simple C programs.
 3. The traditional UNIX name for the C compiler is ‹cc›. On most
    Linux systems (this one included), the default C compiler is
    known as ‹gcc› (short for GNU ‹cc› -- this is mainly because you
    could install ‹gcc› on computers that already had their own
    system ‹cc›).
 4. You can usually run ‹gcc› using the command ‹cc› whenever it is
    the default compiler. I would actually recommend that you do it
    this way, unless you require the GNU compiler specifically. Not
    all modern UNIX systems use ‹gcc› as the default compiler,
    sometimes for a good reason.
 5. You can read the documentation for how to run ‹gcc› using:
    
        $ man gcc
    
    Unfortunately, on this computer ‹man cc› does not work.
 6. The «linker» is available as ‹ld› (probably from Link eDitor,
    some people think it is from LoaDer, but that's more tenuous).
    See also ‹man ld›.
 7. The linker takes multiple binary artifacts (object files,
    libraries) and produces a single file which contains an
    executable program. How this works will be explained in more
    detail in the lectures.
 8. We will not run the linker directly here. This is rarely needed
    or useful even in the real world.

You can continue by looking at ‹hello.c›:

    $ cat hello.c

You can also use ‹vim› or ‹micro› to open it (whichever you normally
use), to make it easier to read:

    $ micro hello.c