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From: Terry Lambert <tlambert@primenet.com>
Message-Id: <199809250648.XAA15367@usr01.primenet.com>
Subject: Re: Limit 'ps' to show only user's processes
To: taob@risc.org (Brian Tao)
Date: Fri, 25 Sep 1998 06:48:18 +0000 (GMT)
Cc: robert+freebsd@cyrus.watson.org, freebsd-current@FreeBSD.ORG
In-Reply-To: <Pine.GSO.3.96.980924094103.16314b-100000@tor-dev1.nbc.netcom.ca> from "Brian Tao" at Sep 24, 98 09:43:53 am
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> > I don't think there is any way to hide the existence of other
> > processes -- a process that performs:
> > 
> > int i, lasti;
> > while (1) {
> > 	i = fork();
> > 	if (!i) {
> > 		exit(0);
> > 	}
> > 	if (i != lasti + 1) {
> > 		
> > ....
> 
>     On a slightly different track, using randomized pid's would limit
> the usefulness of such a scan, although with a fast enough fork(), you
> could still map the entire pid space and find the "holes".

	pid_t	i;
	int	st;
	pid_t	me = getpid();

	for( i = 0; i < MAX_INT; i++) {
		st = kill( i, 0);
		if( st != -1)
			printf( "pid %d exists and is yours...\n", i);
		else if( errno == EPERM)
			printf( "pid %d exists and is NOT yours...\n", i);
	}


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.

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