Show and tell:
	I was just plain lazy and didn't bring anything
	Maybe I'll bring a horrible hacked-together guitar amp next time...

A helpful manual:
https://ftp.gnu.org/old-gnu/Manuals/gas-2.9.1/html_chapter/as_7.html
Note:  It's old, but I don't actually think any of that stuff has changed
	Go read "Deep C Secrets" too, even though it's also old

gas, gcc, ld, as, tools

A few notes:
	.asciz and .ascii:  .asciz null-terminates
	.global and .globl mean the same thing
	I've been paid money to write C/C++, but not assembly
		I'm sure it shows

Alright, interop with C:
	No, you can't just do the class in C now
	I want to show the value of calling conventions
	I also want to show a way you can use a little assembly

Call a C function we wrote from assembly:
	Write the C function in a .c file  (NO main)
	Write the assembly program in a .s file (Include main here)
	Make sure the name of the function is global (or globl)
	Assume the C function follows x86-64 SysV calling convention
	Build like this:
	gcc -static -z noexecstack asm_file.s c_file.c
	gcc will (hopefully!) build you an a.out binary
	(maybe) big caveat:  My demo was br0k3d on FreeBSD
		The heap doesn't work

Let's make an example!

Call an assembly function from a C program:
	Write the C program in a .c file (Include main here)
		(optional) Include a C function prototype
		If you don't do this, the compiler can't do type checking
	Write the assembly function in a .s file (do NOT include main)
	Assume x86-64 SysV calling convention
	Build like this (same as the previous example):
	gcc -static -z noexecstack asm_file.s c_file.c
	gcc will (hopefully!) build you an a.out binary
	
Let's make an example of that too!

Alright, how well do we understand assembly functions?
	Can we write a recursive factorial function?

Do we have to:
	Actually denote sections?
	Declare main global?
	Trigger interrupt 80 at the end?
	Build with gcc?

Did I get here early?
	Alright, let's make up an in-class exercise!