Re: [9fans] directly opening Plan9 devices

[erik quanstrom <quanstro@quanstro.net>]

> Did you see the example I provided in the original
> email? "rfork m" is *exactly* RFNOMNT. And it doesn't
> seem to work for one simple reason: RFNOMNT doesn't
> restrict bind(2).

these are exceptions.  from port/chan.c:

	case '#':
		nomount = 1;
		up->genbuf[0] = '\0';
		n = 0;
		while(*name != '\0' && (*name != '/' || n < 2)){
			if(n >= sizeof(up->genbuf)-1)
				error(Efilename);
			up->genbuf[n++] = *name++;
		}
		up->genbuf[n] = '\0';
		/*
		 *  noattach is sandboxing.
		 *
		 *  the OK exceptions are:
		 *	|  it only gives access to pipes you create
		 *	d  this process's file descriptors
		 *	e  this process's environment
		 *  the iffy exceptions are:
		 *	c  time and pid, but also cons and consctl
		 *	p  control of your own processes (and unfortunately
		 *	   any others left unprotected)
		 */
		n = chartorune(&r, up->genbuf+1)+1;
		/* actually / is caught by parsing earlier */
>>>>		if(utfrune("M", r))
>>>>			error(Enoattach);
>>>>		if(up->pgrp->noattach && utfrune("|decp", r)==nil)
			error(Enoattach);
		t = devno(r, 1);
		if(t == -1)
			error(Ebadsharp);
		c = devtab[t]->attach(up->genbuf+n);
		break;

the first two indicated lines are redundant.
i'm not so sure about any of the exceptions.

- erik