From mboxrd@z Thu Jan  1 00:00:00 1970
From: erik quanstrom <quanstro@quanstro.net>
Date: Mon, 17 Jan 2011 22:39:46 -0500
To: 9fans@9fans.net
Message-ID: <8bbc5989dbab94e0b47d3192d4f2048f@chula.quanstro.net>
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Subject: [9fans] bad juju in devproc.c
Topicbox-Message-UUID: 9e0d1ce0-ead6-11e9-9d60-3106f5b1d025

subtitle: hard linking, chan style.

if you do the chan switcheroo,
you must close the orphan, too.

; diffy -c devproc.c
/n/dump/2011/0117/sys/src/9/port/devproc.c:387,392 - devproc.c:387,393
  		tc->offset = 0;
  		qunlock(&p->debug);
  		poperror();
+ 		cclose(c);
  		return tc;

  	case Qproc:
/n/dump/2011/0117/sys/src/9/port/devproc.c:1183,1190 - devproc.c:1184,1193
  		error(Eprocdied);
  	}

- 	if(p->pid != PID(c->qid))
+ 	if(p->pid != PID(c->qid)){
+ 		cclose(tc);
  		error(Eprocdied);
+ 	}

  	unlock(i);
  	poperror();

it's interesting that the naïve expectation is uniformly
that /proc/$pid/text refers to the image cache, not the
original opened channel.

- erik