code: plan9front

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ircrc: fix race with pipe causing hangup

If the work function opens and closes $netdir/data for an echo
redirection *before* the asynchronous cat process opens it,
aux/trampoline (or tlsclient) will receive a hangup, terminating the
connection.

To fix this, redirect work's stdout to $netdir/data so that it remains
open, and adjust the echo commands accordingly.

--- a/rc/bin/ircrc

+++ b/rc/bin/ircrc

@@ -32,14 +32,14 @@

 fn work {

         if(~ $#serverpass 1)

-                echo PASS $serverpass > $netdir/data

-	echo USER $user foo bar :$realname > $netdir/data

-	echo NICK $nick > $netdir/data

+                echo PASS $serverpass

+	echo USER $user foo bar :$realname

+	echo NICK $nick

 	if (~ $#pass 1)

-		echo PRIVMSG 'nickserv :'identify $"pass > $netdir/data

+		echo PRIVMSG 'nickserv :'identify $"pass

 	if(! ~ $target ''){

 		title

-		echo JOIN $target > $netdir/data

+		echo JOIN $target

 	}

 	if(~ $target *,*)

 		target = `{echo $target | awk -F',' '{print $NF}'}

@@ -46,7 +46,7 @@

 	while (cmd=`{read}) {

 		s=$status

 		if(~ $s *eof) {

-			echo  QUIT : Leaving... > $netdir/data

+			echo  QUIT : Leaving...

 			exit

 		}

 		msg=()

@@ -53,7 +53,7 @@

 		out=()

 		switch ($cmd(1)) {

 		case /!

-			eval `{mshift $cmd} | while(rc=`{read})echo 'PRIVMSG '^$target^' :' $rc | tee $netdir/data

+			eval `{mshift $cmd} | while(rc=`{read})echo 'PRIVMSG '^$target^' :' $rc | tee /dev/cons

 		case /M

 			msg = (MODE `{mshift $cmd})

 		case /N

@@ -101,18 +101,18 @@

 		case /w

 			msg = (WHO `{mshift $cmd})

 		case /x

-			echo  QUIT : Leaving... > $netdir/data

+			echo  QUIT : Leaving...

 			exit

 		case /*

-			echo unknown command

+			echo unknown command >/dev/cons

 		case *

 			msg = 'PRIVMSG '^$target^' :'^$"cmd

 			out = '('^$target^')	⇐	'^$"cmd

 		}

 		if (! ~ $#msg 0)

-			echo $msg > $netdir/data

+			echo $msg

 		if (! ~ $#out 0)

-			echo `{etime}^' '^$out

+			echo `{etime}^' '^$out >/dev/cons

 	}

 }

@@ -248,6 +248,6 @@

 	tlsclient tcp!$server!$port <>$p/data1 >[1=0] &

 }

 netdir=$p

-cat $netdir/data | tr -d '\x2\x8\xd\x1f' | pretty &

-work

+<$netdir/data tr -d '\x2\x8\xd\x1f' | pretty &

+>$netdir/data work