plan9fox/rc/bin/man

#!/bin/rc
# man - print manual pages
rfork e

. /sys/man/fonts

cmd=n
sec=()
S=/sys/man
d=0

fn roff {
	preproc=()
	postproc=cat
	x=`{doctype $2}
	if (~ $1 t) {
		if(~ $x *grap*)
			preproc=($preproc grap)
		if(~ $x *pic*)
			preproc=($preproc pic)
		Nflag=-Tutf
	}
	if not {
		Nflag='-N'
		Lflag='-rL1000i'
		# setting L changes page length to infinity (sed script removes empty lines)
		if (grep -s '^\.(2C|sp *[0-9]*\.)' $2)
			postproc=col
	}
	if(~ $x *eqn*)
		preproc=($preproc eqn)
	if(~ $x *tbl*)
		preproc=($preproc tbl)
	{echo -n $FONTS; cat $2 </dev/null} |
		switch($#preproc) {
		case 0
			troff $Nflag $Lflag -$MAN 
		case 1
			$preproc | troff $Nflag $Lflag -$MAN
		case 2
			$preproc(1) | $preproc(2) | troff $Nflag $Lflag -$MAN
		case 3
			$preproc(1) | $preproc(2) | $preproc(3) |
				troff $Nflag $Lflag -$MAN
		case *
			$preproc(1) | $preproc(2) | $preproc(3) |
				$preproc(4) | troff $Nflag $Lflag -$MAN
		} | $postproc
}

fn page {
	if(test -d /mnt/wsys/acme)
		/bin/page -w
	if not
		/bin/page
}


search=yes
while(~ $d 0) {
	if(~ $#* 0) {
		echo 'usage: man [-bntpPSw] [0-9] [0-9] ... name1 name2 ...' >[1=2]
		exit usage
	}
	if(test -d $S/$1){
		sec=($sec $1)
		shift
	}
	if not
		switch($1) {
		case -b ; cmd=b ; shift
		case -n ; cmd=n ; shift
		case -P ; cmd=P ; shift
		case -p ; cmd=p ; shift
		case -S ; search=no ; shift
		case -t ; cmd=t ; shift
		case -w ; cmd=w ; shift
		case * ; d=1
		}
}
if(~ $#sec 0) {
	sec=`{ls -pd $S/[0-9]* }
}
ix=$S/$sec/INDEX
if(~ $#* 1) pat='^'^$1^' '
if not pat='^('^`{echo $* | sed 's/ /|/g'}^') '
fils=()
if(~ $search yes)
for(i in $S/$sec){
	if(/bin/test -f $i/INDEX){
		try=`{grep -i $pat $i/INDEX | sed 's/^[^ ]* //' | sort -u}
		if(! ~ $#try 0)
			fils=($fils $i/$try)
	}
}
# bug: should also do following loop if not all pages found
if(~ $#fils 0) {
	# nothing in INDEX. try for file of given name
	for(i) {
		if(~ $i intro) i=0intro
		for(n in $sec) {
			try=`{echo $S/$n/$i | tr A-Z a-z}
			if (/bin/test -f $try)
				fils=($fils $try)
		}
	}
	if(~ $#fils 0) {
		echo 'man: no manual page' >[1=2]
		exit 'no man'
	}
}
switch($cmd) {
case p; out=proof
case P; out=page
case *; out=cat
}
{
	for(i in $fils) {
		if(! /bin/test -f $i)
			echo need $i >[1=2]
		if not {
			switch($cmd) {
			case w
				echo $i

			case t
				roff t $i

			case p
				roff t $i | grep -v '^x X html'

			case P
				roff t $i

			case n
				roff n $i | sed '
					${
        				       /^$/p
					}
					//N
					/^\n$/D'

			case b
				x=`{echo $i | sed 's;/sys/man/(.*)/(.*);\1 \2;'}
				if(~ $x(2) 0intro) x=($x(1) intro)
				roff n $i | sed '
					${
        				       /^$/p
					}
					//N
					/^\n$/D' |
				plumb -i -d edit -a 'action=showdata filename=/man/'$x(2)^'('$x(1)^')'
			}
		}
	}
} | $out