Path: utzoo!attcan!uunet!husc6!mailrus!ames!pacbell!ditka!stb!michael
From: michael@stb.UUCP (Michael)
Newsgroups: comp.sys.amiga
Subject: Re: Amiga UNIX
Message-ID: <10458@stb.UUCP>
Date: 1 Jul 88 23:30:12 GMT
References: <23602@hi.unm.edu> <4071@cbmvax.UUCP> <142@ssdis.UUCP> <4109@cbmvax.UUCP>
Reply-To: michael@stb.UUCP (Michael)
Organization: STB BBS, La, Ca, Usa, +1 213 459 7231
Lines: 28

In article <4109@cbmvax.UUCP> jesup@cbmvax.UUCP (Randell Jesup) writes:
>In article <142@ssdis.UUCP> gsarff@ssdis.UUCP (gary sarff) writes:
>>Threads are like shared libraries in the sense that they give you an 
>>advantage if you have more than 1 process using them.  A shared library
>> ...
>>Only if the process is really executing multiple threads of itself do you get
>>any advantage at all.
>
>	This sounds an awful lot like copy-on-write in software.  What happens
>if one of the threads does an exec()?
>
>-- 
>Randell Jesup, Commodore Engineering {uunet|rutgers|allegra}!cbmvax!jesup

Hang on. Multiple threads in a process are just that--multiple execution
points in a single process. Shared data segment. Shared file discriptors.
Shared everything. Think of it like co-routines.

I have no idea what happens on an exec(); my guess is that the entire
process (and all of its threads) go away.

(Want to think of the bizarre? Copy on write with multiple threads,
each of which might do a fork().)
: --- 
: Michael Gersten			 uunet.uu.net!denwa!stb!michael
:				sdcsvax!crash!gryphon!denwa!stb!michael
: What would have happened if we had lost World War 2. Well, the west coast
: would be owned by Japan, we would all be driving foreign cars, hmm...