rc: import latest from 9front

Includes work to increase portability on *nix systems by cinap_lenrek,
some extensions to the syntax, and multiple bug fixes to:
 - lexer/interpreter
 - globber
 - heredoc
and much more.

rcmain

@@ -1,51 +1,38 @@
-# rcmain: Plan 9 on Unix version
+# rcmain: unix version
 if(~ $#home 0) home=$HOME
-if(~ $#home 0) home=/
 if(~ $#ifs 0) ifs=' 	
 '
+profile=$home/.rcrc
 switch($#prompt){
 case 0
 	prompt=('% ' '	')
 case 1
 	prompt=($prompt '	')
 }
-if(~ $rcname ?.out ?.rc */?.rc */?.out) prompt=('broken! ' '	')
-if(flag p) path=(/bin /usr/bin)
-if not{
+if(~ $rcname ?.out) prompt=('broken! ' '	')
+if(flag p) path=/bin
+if not {
 	finit
-	# should be taken care of by rc now, but leave just in case
+	if(~ $#path 0) path=(. /bin /usr/bin /usr/local/bin)
 }
 fn sigexit
 if(! ~ $#cflag 0){
-	if(flag l && test -r $home/lib/profile) . $home/lib/profile
+	if(flag l) {
+		. -q $profile
+	}
 	status=''
 	eval $cflag
-	exit $status
 }
-if(flag i){
-	if(~ $termprog 9term || ~ $termprog win){
-		fn cd {
-			# builtin cd $1 && flag i && awd
-			# is not sufficient when running in a subshell
-			# that is rc -e (like mk uses!)
-			if(builtin cd $1){
-				if(flag i) $PLAN9/bin/9 awd || status=''
-				status=''
-			}
-		}
-		$PLAN9/bin/9 awd
+if not if(flag i){
+	if(flag l) {
+		. -q $profile
 	}
-	if(flag l && test -r $home/lib/profile) . $home/lib/profile
 	status=''
 	if(! ~ $#* 0) . $*
-	. -i '/dev/stdin'
-	exit $status
+	. -i /dev/fd/0
 }
-if(flag l && test -r $home/lib/profile) . $home/lib/profile
-if(~ $#* 0){
-	. /dev/stdin
-	exit $status
+if not if(~ $#* 0) . /dev/fd/0
+if not{
+	status=''
+	. $*
 }
-status=''
-. $*
-exit $status