iff AST_API

ver ast 20111111

api ast 20120528 regexec regnexec regrexec regsubexec strgrpmatch

api ast 20120411 cmdopen

api ast 20110505 cmdopen

api ast 20100601 pathaccess pathcanon pathcat pathkey pathpath pathprobe pathrepl

api ast 20000308 sfkeyprintf

print	#define _AST_VERSION	AST_VERSION	/* pre-20100601 compatibility */