请教大家一个AWK的脚本！

freshyx

最近移植djbdns到ARM上，里面有一个AWK的脚本，我看不太懂，想请大家帮忙分析一下，看看主要是实现什么功能的，多谢大家了！

awk -F: '
BEGIN { OFS=":" }
{
if ($5 == "tx" next
if ($5 == "A" {
print "glue",$6,$3,$4,"answer",$6" A "$7
next
}
if ($5 == "NS" {
print "glue",$6,$3,$4,"answer",$6" NS "$7
next
}
print
}
' | sort -t: +0 -2 +4 +3 -4 +2 -3 | uniq | awk -F: '
{
type = $1
q = $2
c = $3
ip = sprintf("%-16s",$4)

if (q != lastq) { print ""; lastq = q }

if ($5 == "ALERT" {
result = "A\bAL\bLE\bER\bRT\bT:\b: " $6
}
else if ($5 == "answer" {
if (index($6,q" " == 1)
$6 = substr($6,length(q) + 2)
result = $6
}
else if ($5 == "see" {
result = "see " $6
}
else if ($5 == "CNAME" {
result = "CNAME "$6
}
else
result = $5

if (c != "." {
q = substr(q,1,length(q) - length(c))
for (i = 1;i <= length(c);++i) {
ci = substr(c,i,1)
q = q "_\b" ci
}
}

print type,q,ip,result
}
'

waker

NS A tx "A\bAL\bLE\bER\bRT\bT:\b: "看这个应该是过滤一些DNS记录重新格式化排序送给less或什么程序阅读的