zerobase.m4

来自「操作系统SunOS 4.1.3版本的源码」· M4 代码 · 共 34 行

#####		RULESET ZERO PREAMBLE

# Ruleset 30 just calls rulesets 3 then 0.
S30
R$*			$: $>3 $1			First canonicalize
R$*			$@ $>0 $1			Then rerun ruleset 0

S0
# On entry, the address has been canonicalized and focused by ruleset 3.
# Handle special cases.....
R@			$#local $:$n			handle <> form
# Earlier releases special-cased the [x.y.z.a] format, but SunOS 4.1 or later
# should handle these properly on input.

# now delete redundant local info
R$*<$*$=w.LOCAL>$*	$1<$2>$4			thishost.LOCAL
R$*<@LOCAL>$*		$1<@$m>$2			host == domain gateway
R$*<$*$=w.uucp>$*	$1<$2>$4			thishost.uucp
R$*<$*$=w>$*		$1<$2>$4			thishost

# arrange for local names to be fully qualified
R$*<@$%y>$*		$1<@$2.LOCAL>$3			user@etherhost

# For numeric spec, you can't pass spec on to receiver, since old rcvr's
# were not smart enough to know that [x.y.z.a] is their own name.
R<@[$+]>:$*		$:$>9 <@[$1]>:$2		Clean it up, then...
R<@[$+]>:$*		$#ether $@[$1] $:$2		numeric internet spec
R<@[$+]>,$*		$#ether $@[$1] $:$2		numeric internet spec
R$*<@[$+]>		$#ether $@[$2] $:$1		numeric internet spec

R$*<$*.>$*		$1<$2>$3			drop trailing dot
R<@>:$*			$@$>30$1			retry after route strip
R$*<@>			$@$>30$1			strip null trash & retry