Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!auspex!guy
From: guy@auspex.auspex.com (Guy Harris)
Newsgroups: comp.windows.x
Subject: Re: window manager swapping (was Re: Another R5 wish)
Message-ID: <4101@auspex.auspex.com>
Date: 26 Sep 90 18:39:35 GMT
References: <9009041636.AA23617@hansen.com> <489@zok.UUCP> <490@zok.UUCP>
Organization: Auspex Systems, Santa Clara
Lines: 14

>Out of curiosity, on the topic of swapping, do any of the new OS's
>(e.g. System V Release 4, BSD 4.4, OSF 1, etc.) provide a mechanism
>for preventing a specified process from being swapped out?

The "plock()" somebody mentioned in SunOS 4.1 comes from S5 (the API
does, anyway), although I don't know if it prevents any of the shared
libraries being used by the process from being swapped out (either on
SunOS 4.1/S5R4 or on S5R3).  SunOS 4.1 has "mctl()", and S5R4 has
"memcntl()", to lock regions of the address space into memory; 4.4BSD
and/or OSF/1 may have similar calls.

All these calls, of course, require appropriate privilege (typically
super-user privilege).  I wouldn't necessarily be happy if somebody
stuck them into a window manager....