5. awk Patterns: (When there is no pattern, it means all data lines match)
	BEGIN		(preprocessing before all input scanned)
	END		(postprocessing after all input scanned)
	/regular exp. pattern/	
	relational expression pattern
	pattern && pattern
	pattern || pattern
	(pattern)
	!pattern
	pattern,pattern	(scoping pattern involving multiple lines of data)

6. awk Actions:
	A list of zero or more statements separated by ';' or a newline. 
	Braces are used to group statements.  awk supports these actions:

data storage:
	variable = expression
	array[subscript] = expression

conditional statements: [ braces surround statement when statement > 1 command ]
	if (expression) statement [else statement]
	expression ? expression : expression

Iterative statements: [ braces surround statement when statement > 1 command ]
	while (expression) statement
	for (start expression; end expression; increment expression) statement
	for (var in array) statement
	break;
	continue;
	next;
	exit;

Output statements:
	print [expression] > ["expression"]
	print [expression] | ["expression"]
	printf format [, expression ] > ["expression"]

Input statements:
	getline [var] < "expression"
	getline [var]
	"unix command" | getline [var]

Questions? Robert Katz: katz@ned.highline.edu
Last Update April 7, 2005