Note:  I'll make up an active learning exercise about 10 minutes before the end

GUI on Linux:
	Window Manager
	Desktop Environment
	Display Manager
	I'll show you a couple

Time for a walk:  Some computers with names
	Name is often in the prompt
	uname -n
	Separate the computer in front of you from the one you are using
	Since you'll probably ask:  X11 forwarding over SSH
	Remote desktop is another way to do this

Interlude:  Why don't I have to type a password all the time?
	Cryptographic authentication (is stronger, depending)

Let's talk about networks!
	Enough for the moment, anyway
	Internet Protocol
	Addressing with IP
	Ports
	Standard ports

A bit more about how things work
	protocols
	DHCP, briefly, and the MAC address
	DNS, and 8.8.8.8

Ruining the magic kingdom:  Firewalls and NAT
	Some connections can only be initiated from one end
	Port forwarding (for NAT)
	A relay point on the outside
		- ssh can do this

Text editing, and nano
	text file compared to word processors
		- Word processors are for printers
		- So is .pdf
		- Not .html
		- You can eat cake with a spoon (MS Word for code is worse than this)
		- Source code is normally stored in a text file
	nano:  Easy to learn, syntax highlight, generally ok
	gedit: Easy to learn, syntax highlighting, generally ok, needs GUI
	vim:   Not as easy to learn, LOTS of features, has a graphical version
	emacs: Medium learning difficulty, LOTS of features, has graphical version
	code:  A bit different way to work, but avoids editing in remote terminals
	You need to know how to use a text editor to be competent on Linux
		I use vim, but that doesn't mean you should
	
We talked about the file tree a bit yesterday
	But now a tour!
	Slash direction is opposite DOS/Windows
	Case matters!
	/tmp
	/etc
	/home
	/dev and /proc
	/root (and who is root?)
	/bin, /usr, /opt, /sbin, /sys, /lib, /lib64
	/var and /var/log
	/usr/share/doc

Special characters in filenames:
	Spaces 
	/
	- (not special)
	. (not special)
		Linux does not require file extensions
		They are commonly omitted on regular text files
	~ (your home directory, if it is first)
	cd with no parameters

Note:  This next part is important for lab
Let's learn another command:  grep  
	grep and files
	grep and pipes

If we get this far:  Writing a program with C
	We'll use the text editor again

Finally:  pipes (combining grep and who)

Warm-up (not really review):
	Which set of notes was longest?
	What processors are on systems I can ssh into?

Standard Input, Standard Output, and Standard Error
	Redirection operators on the command line

Ok, time to look at the inside
	By understanding the inside, you will understand the outside too
		When you get a new car, don't you take it to bits first thing?
	C brief intro
		Came before C++
		It's the language Linux is written in
		Standard programming language for *nix
	I'll assume you know the first 3 chapters of the C++ text
	Differences from C++:
		header files end with .h
		No namespaces
		No classes (including cin and cout)
			And string
		No standard template library
		Nested functions are ok
	C++ is nearly a proper superset of C
		No nested functions, unless you use lambda
		Struct initialization is more verbose
		Casting rules produce more warnings
	C++ has become very popular for *nix programming
		K desktop environment, for example
		It's like C, but has more features
	I'll use actual C for all examples in this class
		In CS430, you will too, because the kernel is not in C++
		You're welcome to use C++ in this class if you like!
		Less confusing if you're in CS211 at the same time
		I'll also try to make sure the examples all work in C++

File descriptors, and read/write
	write system call (what is a system call?)
	We'll open a file and write to it
	How about just using 1 as the file descriptor?
	0, 1, and 2, and write
	How about changing the file descriptor a program writes to?
		>, and file redirection
		2> redirects standard error
	
Parallel for standard in:
	It's file descriptor 0
	We can use the read system call to read from it
	

Let's make a program that just passes things through, and then redirect a file into it!
	Infinite loop, read, then write
	cat can do this.
	Maybe do something trivial, like capitalize all letters

A very useful program:  grep
	Searches through standard input or files

Permissions
	User, Group, Other
		All, which is different from other
		All is used with letters for chmod
	setuid root for programs
		Demo, with c program and system
	sticky bit and /tmp
		Undo sticky and see what happens!