Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!lll-tis!ames!sdcsvax!rutgers!husc6!encore!paradis
From: paradis@encore.UUCP (Jim Paradis)
Newsgroups: comp.os.minix
Subject: Re: Job control?
Message-ID: <2596@encore.UUCP>
Date: 1 Feb 88 02:38:59 GMT
References: <712@silver.bacs.indiana.edu>
Sender: news@husc6.harvard.edu
Reply-To: paradis@encore.UUCP (Jim Paradis)
Organization: The Whizzo Chocolate Company
Lines: 28

In article <712@silver.bacs.indiana.edu> creps@silver.UUCP (Steve Creps) writes:
>   I've just started checking out Minix, and have a question on
>job control. Namely, how much is supported? In Ultrix I can run
>a job, type ^Z to suspend it, then type fg or bg to restart it
>running in foreground or background. Does Minix support anything
>like this? If the supplied shell doesn't do this, would it still
>be possible to write another shell that does?

Sorry, but job-control currently does not exist in MINIX, and it would
be non-trivial to add support.  I plan to do this someday (I even have
hooks in my TTY driver for its eventual support), but I have no idea 
exactly when.  Off the top of my head, if you wanted to support job 
control you would have to AT LEAST do the following:

	(1) Add support for stopping processes.  This involves
	    adding a new process state (STOPPED) and modifying
	    the scheduler to know not to activate such processes.

	(2) Add support for the equivalent of the wait3() system call.

	(3) Modify the shell (or preferably write a C-shell clone) to
	    take advantage of the new support.

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