rbetel@watcsc.waterloo.edu (Richard Betel) (10/13/89)
It seems to me that job control is jus a way of having several interactive
programs running (or waiting) at once. Isn't this a pretty common feature
of Xwindows?
Now for my real message:
I just ordered Minix from P-H. Unfortunately, I didn't know the most
recent ISBN number (AST posted it 2 days later) at the time, and so I
asked for the one listed in the back of the book. It occured to me a bit too
late that I might just end up getting an extremely old revision of Minix.
How do I go about upgrading it to 1.4b?
I am running an 8MHZ clone with a 65M hard drive and a 1:1 interleave
DTC controller. Should I anticipate big problems with installation?
Richard Betel
(rbetel@watcsc.waterloo.edu)rwa@cs.AthabascaU.CA (Ross Alexander) (10/16/89)
The really useful things you get out of job control are SIGURG, SIGIO,
SIGSTOP, and SIGCONT. Tty handling is nice but secondary. A windows
or virtual-tty hack would do that part of it well enough. SIGWINCH
would be handy for the windowing stuff.
What about it? SIGSTOP and SIGCONT should be pretty straight forward.
I wouldn't mind seeing an implementation of (2) select(), either.
Yes, I know, write it yourself. I promise to start.
Ross
ps: why do I want SIG{STOP,CONT} ? Every try to use ^S to stop a job
that wasn't writing to the tty? Worked pretty poorly, didn't it ;-)?
rjonah@db.toronto.edu (Jeffrey Lee) (10/16/89)
rwa@cs.AthabascaU.CA (Ross Alexander) writes: >The really useful things you get out of job control are SIGURG, SIGIO, >SIGSTOP, and SIGCONT. Tty handling is nice but secondary. A windows >or virtual-tty hack would do that part of it well enough. SIGWINCH >would be handy for the windowing stuff. > >I wouldn't mind seeing an implementation of (2) select(), either. Most people have no bone to pick with these. It's SIGTSTP and all of the goo related to having to suspend a process that tries to write to a terminal when it's not its turn. --- Disclaimer: My opinions are someone else's, so don't blame me.
ast@cs.vu.nl (Andy Tanenbaum) (10/16/89)
In article <1166@atha.AthabascaU.CA> rwa@cs.AthabascaU.CA (Ross Alexander) writes: > >The really useful things you get out of job control are SIGURG, SIGIO, >SIGSTOP, and SIGCONT. Ah ha! Another nice reason for not doing job control. The signal() call does not exist in POSIX. Instead there is something called sigaction(), which uses bit maps. To conform to POSIX I need 15 signals, plus an extra quasi-signal for detecting stack overflow in protected mode. Thus the bit map is naturally an unsigned short, and is full. Job control would mean going to longs for everything (or mediums--24 bits). Furthermore, SIGURG and SIGIO do not exist in POSIX, not even if _POSIX_JOB_CONTROL is defined. SIGSTOP and SIGCONT do exist. Andy Tanenbaum (ast@cs.vu.nl)
jk0@image.soe.clarkson.edu (Jason Coughlin) (10/16/89)
I'm a little confused by this discussion about job control. Could some kind soul please fill me in on the details (maybe my email, but I'm sure others are as confused as me). I thought job control was handled by the csh with things like this: % emacs & % ls -l % fg %1 (then hit cntl-z sometime) % rsh sandbox.mcs "ls -l" temp & % rsh sun.soe "ls -l " temp & % fg %2 % fg %1 etc, etc, etc. -- Jason Coughlin ( jk0@sun.soe.clarkson.edu , jk0@clutx ) "Every jumbled pile of person has a thinking part that wonders what the part that isn't thinking isn't thinking of." - They Might Be Giants