UNIX-WIZARDS-REPLY-DIGEST-SORT-OF (not really a digest file)

[BostonU SysMgr]

Ok, I guess an appropiate way to deal with unix-wizards-digest
is unix-wizards-reply-digest-sort-of:

Todays Topics:
		    Laser printers and 8-Bit serial
		       Group accounting on 4.2bsd

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To lund at ucla-cs, Re: Laser printers and 8-bit serial

You are confusing input with output. TANDEM means when the
tty input buffer is in danger of overflowing (an arbitrary
high water mark) the system PRODUCES a ^S and, when it drops
back down to a 'safe' level (arbitrary low water mark) it PRODUCES
a ^Q to signal that you can resume stuffing the tty line.
This should have no particular effect on RAW input (as you mention,
feeding a ^S to emacs.) That is an INPUT ^S, not an OUTPUT ^S.

As the world becomes more networked login paths are becoming less
transparent. Many switches and terminal servers reserve a few chars,
typically (like our Ungermann/Bass) ^S/^Q for flow control, some sort
of disconnect character or at least a 'wakeup', and quite possibly a
DLE (eg. ^P for literally quote next character, this is the ASCII DLE.)
What happens is that the switch, being overloaded, wants to send a
^S to the system to stop flow for a while.

I *strongly* suggest people start fixing software universally to accomodate
this rather than fighting it. All EMACS' that I know of allow re-definition
at the user level of ^S/^Q to some other keys.
Another popular program with this problem I just fixed is script.c .

I suggest the following for fixing software in 4.2:

	a) Use CBREAK mode, (Probably ECHO and CRMOD off)
	b) Set all of tchars and ltchars to 0xff except
	the startc/stopc.

On SYSV just shutting off ICANON and ISIG (with appropiate timing dances)
does a similar thing. I use this in our Emacs' and other software and
have had no problems.
Doing this will also stop those 9600 baud VT[12]00 ttys from hanging.

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To vidar at kvvax4, Re: group accounting on 4.2bsd
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At BU when we create an account our script takes one of two forms:

	makusr username
	makusr username principle

The former creates a 'group leader' which mean that UID==GID, this
can be a dummy account or the actual person in charge. The latter
creates an account with a new UID but GID the same as the 'principle'.
Using this you will have to consider any group access permission
problems, perhaps UMASKS should be set up appropiately.

At that point it is just a matter of gathering (eg. sort or grep) by same
gid to produce group accounts, probably a simple program to add up
columns thus created to produce group accounting.

P.S. One strange omission (to my knowledge) from all the UNIX tools
is a program, similar in command syntax (groan, but probably needed)
to 'sort' which adds up columns of numbers:

	sumcol +4.6 foo

Strange, must have been written hundreds of times.
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*End of UNIX-WIZARDS-REPLY-DIGEST-SORT-OF

	-Barry Shein, Boston University