plan9fox/rc/bin/lookman

#!/bin/rc
# Usage: lookman key ...
#	prints out the names of all manual pages containing all the given keywords
rfork e
index=/sys/lib/man/lookman/index
t1=/tmp/look1.$pid
t2=/tmp/look2.$pid
fn sigexit {
	rm -f $t1 $t2
	exit
}
fn sigint sighup sigterm {
	rm -f $t1 $t2
	exit note
}

*=`{echo $*|tr A-Z a-z|tr -dc 'a-z0-9_. \012'}	# fold case, delete funny chars
if(~ $#* 0){
	echo usage: lookman key ... >/fd/2
	exit usage
}
look $1 $index | sed 's/.*	//' | sort -u >$t1
shift
for(i in $*){
	look $i $index | sed 's/.*	//' | sort -u |
		awk 'BEGIN {
			while (getline < "'$t1'" > 0)
				table[$0] = 1
			}
			{ if (table[$0]) print }
		' > $t2
	mv $t2 $t1
}
sort $t1 | sed 's;/sys/man/;;
	s;(.*)/(.*);man \1 \2 # \2(\1);'
exit ''