Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!hao!gatech!galbp!bing
From: bing@galbp.LBP.HARRIS.COM (Bing Bang)
Newsgroups: comp.os.minix
Subject: Re: I am seeking test program that hangs the system
Message-ID: <4313@galbp.LBP.HARRIS.COM>
Date: 1 Mar 88 15:35:06 GMT
References: <1234@louie.udel.EDU>
Reply-To: bing@galbp.UUCP (Bing Bang)
Organization: Harris/Lanier, Atlanta, GA
Lines: 31

In article <1234@louie.udel.EDU> V050KY8G@ubvmsc.cc.buffalo.edu writes:
> I remember seeing a description in the DL section of
>CompuServe something about a "multitasking FS"... was this implemented in 1.2?

i've been working with a multi-tasking fs for some time now... here's a progress
report.

in my fs, all messages between fs and the tasks are handled asynchronously,
except for those that involve a access to a file system.
to do this without causing deadlocks i had to provide a system que for messages
waiting to be sent. this means a sender will never get blocked.
this change made possible running back ground processes even with the tty
stopped on a foreground job. it also made it possible for me to do the following

- inform() no longer exists. messages always get through
- implementation of named pipes. i use it as a cheap ipc
- implementation of global semaphores. i made them a special file that aquires
  the semaphore by reading from it and releases it by writing to it. no new
  system calls needed! :-)
-tty signals go through fs who know who owns the tty. a compromise, but it works

i really had to tear the guts out of fs. posting my work will be a major under-
taking, besides i took stuff out that some people may still use, like the ram-
disk (i boot onto a hard drive directly). but i am in the process of setting up
a local bbs ("The MINIX Corner") which will have download capabilities. perhaps
this is the solution...


-- 
Bing H. Bang      +--------------------------------------------------------+
Harris/Lanier     |OS/2 on PS/2: Half an operating system on half a machine|
Atlanta GA        +--------------------------------------------------------+