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The

Alto-Dolphin-Dorado

Briefing

Blurb

or

Exploring

the

Ethernet

with

Mouse

and

Keyboard

BY

LYLE

RAMSHAW

A

revision

of:

A

Field

Guide

to

Alto-Land,

by

ROY LEVIN

This document is

for

Xerox internal use only

MAY

1981

XEROX

PALO

ALTO RESEARCH CENTER

3333

Coyote

Hill

Road /

Palo

Alto

/

California

94304

Raison

d'Etre

Are you a programmer? Are you sick

of

manuals that tell you how to use a software system

without telling you

why

it behaves as it does? Are you flustrated because you don't know the

unstated assumptions behind the interesting discussions you hear around

you?

Have you ever

wanted to browse through the source code or the documentation for a program, but couldn't figure

out where to find

it?

If

the answer to some

of

these questions

is

"yes", read

on!

These and other

useful (and occasionally entertaining) tidbits shall be made known unto you.

You

will

doubtless read many documents while

you

are

at

Xerox. A common convention observed in many manuals and

memos

is

that fine points or items

of

complex technical content peripheral to the main discussion appear in small type,

like this paragraph. You

will

soon discover that

you

cannot resist reading this fine print and that, despite its diminutive

stature, it draws your

eyes

like a magnet. This document has such passages

as

well, just so that you can begin to enjoy

ferreting out the diamonds in the mountain

of

coal.

There

is

a great deal

of

useful infOlmation available on-line

Oat

Xerox in the form

of

documents and

source program listings. Reading them

is

often very helpful, but finding them can be a nuisance.

Throughout this document, references to on-line material are indicated by

{n},

where n

is

a citation

number in the bibliography at the end

of

this document. Standard citations to the open literature

appear as

[n).

Reading a document from front to back can be mighty boring. This document

is

organized so that

you can (supposedly) browse through and read the parts that look interesting. In

fact,

the current

version

of

this document

is

so

disorganized that it

is

not at all clear that there really is a front and a back in the normal

sense!

This means that the usual bottom-up approach to documentation (define your terms before

you use them) has been abandoned. Instead, all the relevant terms, acronyms, and the like have

been collected in a glossary at the end. Some information is contained only in the glossary, so you

may want to scan through it later (or

now,

for that matter). It

is

assumed that you have a basic knowledge

of

computer science, and a modicum

of

common

sense.

Don't expect

to

find terms like "computer" and "network" in the

glossary.

The Alto-Dolphin-Dorado Briefing Blurb 2

Alto-

Dolphin-

Dorado"

Land

Behind that inviting screen there lurks a wealth

of

fascinating history, folklore, and (occasionally)

documented wisdom. However, even the great storytellers

of

old occasionally forgot that their

attentive audiences included travelers from other lands who

were

ignorant

of

the local customs and

traditions.

So

it

was

with the Alto gurus. What follows

is

a transcription

of

the oral history

of

the

Alto culture acquired

by

a relatively recent settler

in

these parts.

It

makes no claim to

completeness, balance, or fairness.

(A

separate document exhibiting these qualities may be found

on {20}.)

Before exploring Alto-land,

you

should know something about the names

of

the creatures

you

will

find there. The prevailing philosophy about naming systems in CSL and SDD

is

perhaps somewhat

different from the trend elsewhere. While

we

have our share

of

alphabet soup (e.g., PARC,

FfP,

MAXC, IFS),

we

are trying to avoid making it any worse. Names for hardware and software

systems are frequently taken

from

the Sunset Western

Garden

Book

[14];

Grapevine servers are

named after wines; Dorados are named after capital ships; Pilot releases are natned after California

rivers. Personal machines also have names that frequently, but not

necessarily,

come

from

the same kinds

of

sources.

These

names are chosen

by

the machine's owner, and registered

with

an

entity named NetSupport

WBST.

As

this

convention about names does not meet with universal approval, it seems inappropriate

to

offer a

justification

of

the underlying philosophy without offering equal time to the opposition. You will

doubtless provoke a far more interesting discussion

if

you advance your own

views

on naming to

almost anyone wandering in the corridors. Accordingly,

we

abandon the topic here and move on to

more concrete matters.

Alto, Dolphin, and Dorado

hardware

Most

of

the offices and some

of

the alcoves around PARC have personal computers in them

of

one

flavor or another. The first

of

these

was

the

Alto.

There are more than

1000

Altos in existence

now,

spread throughout Xerox, the four universities in the University Grant program (through which

Xerox

has

given

Altos

to

U.

of

Rochester, and

Altos,

Dovers, and IFS's

to

eMU,

MIT, and Stanford), and other

places. In contrast, the Dolphin and Dorado are newcomers to the scene. A Dolphin

is

somewhat

more powerful than an Alto, and a Dorado

is

gloriously more powerful. Private ownership

of

Dorados

is

a recent innovation, and has not yet spread very

far.

Most

of

us get our

fixes

of

Dorado

time by signing up on lists to share one

of

the "pool" Dorados.

The Alto

hardware

The genus "Alto" comprises

two

species, imaginatively named Alto I and Alto II, and there are

several sub-species

as

well.

All

members

of

the genus have at least a display, a keyboard, a mouse

with 3 buttons, and a processor/disk cabinet. The front cover

of

an Alto I cabinet has a ventilation

grill just at the bottom, while on the front cover

of

an Alto II, the grill goes all the

way

up to the

disk slot.

All

Alto I's have a main memory consisting

of

64K 16-bit words, called one bank in local

parlance. Most Alto II's are equipped with the extended memory option (XM), and have up to

four banks

of

memory (that

is,

256K 16-bit words). Needless

to

say, you can do it lot more with

four times the memory.

The first Alto II's made came equipped

with

a funny keyboard, properly called the

ADL

keyboard,

although sometimes

also

simply referred to as the Alto

II

keyboard

An

ADL keyboard

is

larger,

and has a different

key

layout, including

columns

of

function

keys

on the left and right. The ADL keyboards were generally reviled, and hence did not stay in

production

long.

Nowadays, they are pretty rare.

If

you

want to see one, check out Clover's Alto. Don't be confused

by

documentation that warns

you

that

keys

will

be in different places on an Alto II;

you

can

safely

ignore these

The Alto-Dolphin-Dorado Briefing Blurb 3

warnings unless, God forbid, your

Alto

II

has

an

ADL keyboard.

The innards

of

the Alto are revealed in gory detail in a very complete manual {I}. Facts, figures,

specifications, and programming information (at the machine level) are

all

there. What isn't there

is

a bit

of

the philosophy underlying the machine design and organization. In particular

...

1)

There isn't much special-purpose hardware in the Alto. Most

of

the nifty stuff you can

read about in the hardware manual

is

in fact implemented

by

microcode. This gives us

considerable flexibility in the

way

we

design software interfaces for experimental devices

and specialized instruction sets. In

fact,

Mesa and Small talk are implemented almost entirely with

"special" microcode.

2)

The display

is

rather different from a number

of

other common displays. Instead

of

containing a character or vector generator, the display hardware interprets individual bits.

One bit in memory shows up

as

one dot on the screen. Since the screen

is

606

by

808

points, a quick calculation shows that a full-screen display requires nearly half

of

an Alto I's

memory. For a machine with only 64K

of

memory, that seems a big price to pay. The

theory

is

that in exchange for the space

we

get enormous freedom

to

experiment with

various strange

ways

of

manipulating the screen.

So

much for philosophy-how does it work out in practice? Well, excessive flexibility breeds chaos,

so

a number

of

things have been standardized.

All

Altos contain a ROM that defines the "normal

emulator"

(Le.,

the standard instruction set) and the standard

i/o

device interfaces (e.g., display,

disk, ethernet, and so-called "junk

i/o"-the

keyboard and mouse). The instruction set

is

derived

from the Data General Nova, though the

ilo

structure

is

rather different and several specialized

instructions exist to support various display manipulations.

If

you

have a spare hour or

so,

read about

BITBLT

in {I}. Then

try

to imagine writing the microcode to implement

it

Since the microcode for these

standard facilities

is

blown into a ROM, suggestions for improvements/extensions are treated with

considerable skepticism. Microcode hackers

will

find the additional 1K control RAM available on

all Altos a reasonably comfortable sandbox

in

which to play.

If

you

are both a microcode hacker and a

concrete pourer, you can also use a second

lK

of

ROM

on Alto II's. A

few

Alto II's substitute 3K

of

RAM

for

the

second

lK

of

ROM, which

gives

you

even more room to play without any need

for

concrete

..

The display has enormous potential, and there are a number

of

programs around that exploit it in

interesting

ways.

We also

feel

compelled to note that at least an equal number

of

programs still

treat the display

as

a glass teletype. Home-made cookies require more effort,

but

they taste a lot

better than the store-bought variety. Fortunately, more and more people are getting into home

cooking.

The mouse has two -obvious

properties-it

rolls and it clicks. Inside the Alto hardware, the mouse

position and the display cursor position are completely unrelated,

but

most software arranges for the

cursor to "track" the mouse's movements. The three mouse buttons are named red, yellow, and

blue, even though physically they are nearly always black. This choice

was

made because not all

mice have their buttons arranged in the same

way.

On some (older) mice, the buttons are thin,

horizontal bars; the top one

is

red, the bottom one

is-

blue. On most mice, however, the buttons are

wide, vertical bars, with red at the left and blue at the right. Some people insist on naming the buttons red,

yellow,

and

green-perhaps

as

kids they had strange paintboxes, or were fixated on traffic lights.

A somewhat unusual property

of

the Alto

is

that the keyboard and mouse buttons are unencoded;

that

is,

there is a bit for each

key

that indicates whether the

key

is

up or down. Many programs

The Alto-Dolphin-Dorado Briefing Blurb 4

distinguish between holding a mouse button down and clicking it down and up. Fewer programs

play such tricks with the keyboard, although combinations

of

keys that would jam a conventional

typewriter are quite meaningful to some programs,

c.g.,

the NetExec. Fortunately, there

is

standard

software that enables you to treat the keyboard in the usual

way

if

you want to. Note that this "usual

way"

involves a feature called infinite

rollover

that changes your typing

style

after a

while:

you

can have arbitrarily

many

keys

depressed at the same time without causing a jam, and without causing any strokes to be discarded. Every

key

that goes

down

counts as a

key

stroke when it goes

down,

and when that

key

comes up again doesn't matter at

all.

A

few

weeks

of typing on this sort.

of

keyboard, and

you

begin typing common letter clusters such

as

"ion" with just a

flick

of

the wrist; after

all,

if the letters come out in the wrong order on the display screen,

you

can always edit them

later.

With a personal computer, you are programmer, system hacker, and console operator all rolled into

one.

If

you don't like the state your program has reached, you can always press the boot button

and start

over-an

option you rarely have on larger, shared machines. It

is

a good idea NOT to press the

boot button when disk activity

is

in progress, however, since

you

may

interrupt the writing

of

a disk sector halfway

through, thus rendering that sector unreadable. However, the Alto differs from many small computers in

that it lacks those time-honored, nitty-gritty debugging facilities: the console lights and switches.

If

things are

so

screwed up inside that you can't get some sort

of

(software) debugger running, there

isn't much

you

can do

as

console operator. This tends to down-play the operator role and

emphasizes the system hacker role. ("Let's

see,

if

I hit shift-Swat, that will write the core image

on

Swatee, and

if I then bootload the debugger

...

fI)

It

also makes certain kinds

of

bugs, e.g., those that smash crucial

memory locations in low-core, very difficult to find.

If

you have just turned

on

an Alto and are about to spin up your disk and

do

some work, it

is

a good idea to hit the

boot button

be/ore

your disk comes up to speed: When an Alto

is

first powered up, it comes up in an unknown state,

and there

is

some small but nonzero chance that the processor

is

sitting in a loop just waiting to eat your disk (that

is,

write something on it).

Double Disks on Altos

Many Altos in CSL have been equipped with a second disk drive, which either balances on top

of

the processor cabinet or sits on some flat surface nearby. The

two

drives

of

a double disk Alto can

be used in two different

ways:

either the

two

disks constitute separate file systems, or they together

constitute a single, larger

file

system.

It

is

possible to extend a one disk Alto file system into a two

disk system at any time, but the reverse

is

not possible. And a two disk system will only operate

when both

of

its disks are loaded into the drives

of

a double disk Alto. A double disk machine has

a second little switch hidden at the back

of

the keyboard, in addition to the boot button. This

switch serves to interchange the roles

of

the two drives, called

DPO

and

DPl.

If

you

flip

this switch

while disk activity

is

in progress,

you

will

fairly likely get what

you

deserve: a smashed page on

o~e

or both

disks.

The

Scavenger

may

help

you

recover.

The

Dolphin

(formerly

called

the

DO)

A Dolphin looks a lot like an Alto II. The biggest difference

is

that the Dolphin has a nasty

looking piece

of

solid sheet metal where an Alto has a slot into which you can stick your disk pack.

You see, a Dolphin comes with a Shugart

4000

disk instead

of

the Diablo

31

disk

of

the

Altos-and

the recording medium

of

a Shugart 4000

is

not removable

(well,

not

easily

removable anyway: with the

right tools and expertise, you might

swap

platters in an hour or so). This makes it somewhat harder to borrow

someone else's Dolphin than it

is

to borrow their

Alto-see

the discussion below on Living Cleanly.

Dolphins have various advantages over Alto II's: Mesa programs run significantly faster; long

pointers in Mesa work (making it easier to use lots

of

memory); the Shugart disk is bigger (two

The Alto-Dolphin-Dorado Briefing Blurb 5

partitions); and Pilot runs on Dolphins. Most Dolphins have wide displays, 1024 bits in width

instead

of

the

606

bits

pf

the standard Alto-style display. The extra screen space

is

only available to

programs running in the Pilot world.

The

Dorado

(very

formerly

called

the

D1)

A Dorado doesn't look anything like an Alto, although most Dorados today come equipped with an

Alto-style terminal (display, keyboard, and mouse). In

fact,

in a return to the

ways

of

the past, a

Dorado's processor

is

located in a remote, heavily air-conditioned machine room. When the Dorado

was

being designed, it

was

intended and hoped that the Dorado,

like

the

Alto,

would

live

in your

office.

To prevent its

noise

output from driving

you

crazy,

a

very

massive

case

was

designed, complete with many pounds of sound-deadening

material. These

cases

are fondly known

as

APC's, although

no

one

is

sure what the letters stand

for

in the Dorado's

case

(see the Glossary). But experience indicated that Dorados run too hot when inside

of

these cabinets. and the

concept

of

having Dorado processors in offices has been abandoned. With

VLSI

and

all,

there

is

some hope that the

Dorado's successor (the Dragon?)

will

once again come out

of

the machine room and into your office.

Dorados have varying amounts

of

memory, but at least 512K 16-bit words, or equivalently, 8 banks.

In addition

to

these oceans

of

real memory, the Dorado has a

fairly

whippy processor, a cache, and

a Trident

80

MByte disk; this all adds up to pretty impressive perfonnance. A Dorado

is

roughly

three to

five

times faster than an Alto when emulating an Alto, that

is.

running

BCPL.

And a Dorado

runs compute-bound Mesa software roughly eight

to

ten times

as

fast

as

an Alto. Because

of

the

raw

power

of

a Dorado, it

is

usually the computer

of

choice for substantial programming projects.

The primary difficulty about Dorados

is

that there aren't enough

of

them-yet

(and the related fact that

they are rather

tricky

to build).

Dorado disks can be changed with somewhat greater ease than Dolphin disks, but the process

is

still

painful enough that changing disks

is

not the normal mode

of

operation. The biggest difficulty

is

that you must be at the processor to change the disk, and the processor

is

a long

way

away.

Subsidiary difficulties are that you must power down a Dorado in order to change the disk pack,

and that T-80 disk packs are difficult

to

label effectively.

As

a result, when you borrow a Dorado,

you also need

to

borrow at least some

of

the space on that Dorado's local disk: this brings us to

the issue

of

Living Cleanly.

Living Cleanly: local disks, file

servers,

and the like

Local disks are very convenient, but not very reliable.

It

is

quite tempting to work along on an

Alto for weeks at a time, without backing up your

files

on any other medium. You might be able

to

do this forever without getting burned. On the other hand, those

of

us

who have been hanging

around here for a while could tell you many sad stories

of

head crashes and dropped disks, that left

our colleagues (or even ourselves) with disk packs suitable only for wall decorations. In

fact,

most

of

those very

disks

are

now

serving

as

wall

decorations. Hence, the principle

of

clean living: you are living

cleanly

if

your pulse and blood pressure would remain substantially constant when you are

infonned that your local disk has been degaussed. Make sure that all

of

the bits you really

wouldn't want

to

lose are out some file server, such

as

Maxc or an IFS, where suitable precautions

are constantly being taken

by

wizards

to

protect against disk failure. Appropriate use

of

command

file,

dump

files.

and other automatic aids can make this task easier.

Encouraging clean living has another benefit: shared local disks are only practical

if

everyone lives

cleanly. The management

of

the public partitions on Dolphins and Dorados presumes a policy

of

clean living: when you are done working on a public partition, you must store away all

of

your

files

on remote

file

servers. It

is

polite to delete your

files

from the

local

disk

as

well,

to give whoever

follows

you

The Alto-Dolphin-Dorado Briefing Blurb 6

more space to play; but this

is

not nearly

as

critical.

If

you

find that there isn't enough space on a

partition,

you

are perfectly within your rights

to

delete the random

files

that are lying around on

the partition

to

regain space. And the creators

of

those

files

won't mind, it

says

here, because they

have been living cleanly. In

fact,

there

is

an authoritative image

of

what a "completely clean" public Alto-Mesa 6

partition

for

a Dorado

is

out on [Ivy]<Cedar)Mesa6.bfs.

If

you find that the public Mesa partition you just started using

seems to be screwed up in some

way,

you can always get back to a known good state with lots

of

free space by

smashing the whole partition with that image, using CopyDisk.

(fhe

above paragraph

is

the "letter

of

the law" regarding the sharing

of

public partitions. People

who

want to be

well

regarded should

also

pay some attention

to

the "spirit

of

the law": sharing

things

is

always more pleasant when everyone acts with a modicum

of

politeness and care. This

topic

is

discussed at greater length below

...

)

It

would

be

nice

if

our computers could handle more

of

this

file

shuffling

for

us.

There

is

some hope that

we

will

be

able to move someday

to

a glorious future in which all

of

the independent

file

system

fiefs

will be combined into a

universal

file

system, and all

local

disks

will

be employed simply as automatically-managed caches for that

file

system.

A few comments

on

Booting

An Alto has one boot button, hidden behind the keyboard. On Dolphins, there are two boot

buttons, one at the back

of

the keyboard, and one on the processor cabinet itself: the

two

perform

roughly the same function, but the one on the cabinet

is

a little more potent. On Dorados, the

situation

is

much more complex. There are really

two

computers involved, the main processor and

a separate microprocessor called the

baseboard

computer.

It

is

the baseboard computer's job to

monitor the power supplies and temperature, and to stage-manage the complex process

of

powering

up and down the main processor, and the correct initialization

of

all

of

its RAM's. The boot button

on a Dorado

is

actually a

way

of

communicating with this baseboard computer. You encode your

request to the baseboard computer

by

pushing the boot button repeatedly: each number

of

pushes

means something different. For details, see Ed Taft's memo: {24}.

If

the baseboard computer

of

the Dorado has gone west for some reason (as occasionally happens), your only hope

is

to

push the

real

boot button, a little white button located on the processor chassis itself,

far,

far

away. Just

as

the

boot button on the keyboard

is

essentially a one-bit input device for the baseboard computer, the baseboard computer

also has a one-bit output device: a green light located on the processor

chassis.

Various patterns

of

flashing

of

this light

mean various things,

as

detailed in {24}.

Small

Fish

in

a Big

Pond-the

Network

Two's company, three's a network. You can do a lot with an Alto,

but

at best it's still a classy

minicomputer. With hundreds

of

them out there

we

should be able in theory to do all sorts

of

wonderful things. In practice,

we

actually do some

of

them. You should read the paper by

Metcalfe and

Boggs

describing the Ethernet

[2]

for a good introduction to the communication

network that connects our Altos together. In essence, a collection

of

Altos within reasonable

proximity

is

hooked together by an Ethernet. Ethernets are connected

to

each other by Gateways,

which for most purposes allow us to ignore the topology

of

the

reSUlting

network; the network as a

whole

is

called the Internet. However, occasionally it's nice to know where things

really

are, and

that's when a map {3}

is

helpful. For programs (which are notoriously poor map readers), the Gateways also

provide an information service {IS}.

We all know how uncommunicative computers can be when left to their own devices, and Altos are

no different That's

why

we

invent careful protocols for them to use in talking to each other. Most

of

the protocols now in use on the Ethernet are called PUP·based <rARe Universal

~acket)

{16}.

The Alto-Dolphin-Dorado Briefing Blurb 7

Built on top

of

the Pup protocol are quite a number

of

others, some

of

which you can read about

in

{4,5,6,7}. You

will

probably hear

SOlne

of

the following protocol names being tossed about in

conversation:

1)

EFfP

-stands variously for Early FTP, Ears

FfP,

Experimental

FfP,

Ether

FfP,

Easy

FrP.

A venerable protocol

now

Inostiy used

to

transfer

files

to

printing servers. The Alto

program EmPress uses it for this purpose.

2)

FrP

-refers

to

the File Transfer Protocol,

as

well

as

the Alto program that implements

it and provides an interactive user interface.

If

you come

from

the Arpanet world, don't

confuse this FTP with the one out

there-ours

is

Pup-based and incompatible. On MAXC,

where both the Pup and Arpa FTP protocols come

in

handy, the name

FfP

refers to the

Arpa one and PupFTP (obviously) refers to the Ethernet one.

3)

BSP

-the

Byte

Stream Protocol. Built on top ·of Pup, this protocol

is

used by

conversants

who

want

to

view

the network

as

a full-duplex stream

of

8-bit bytes.

BSP

is

used to implement

FIP

and Chat.

4) The Grapevine Protocols. Grapevine

is

a distributed message transport system, and

clients

of

this system, such

as

Laurel, use a special set

of

protocols to interact with it.

There are quite a

few

other protocols in use

as

well.

The wisdom here

is:

if

you have some nifty

multi-machine communication

to

do, look around-someone may well have done your protocol

work

for

you.

There also are a number

of

communications wizards about

who

can keep you from

falling into various traps.

Question: Why have a network? Answer: Because it's nice to be able to pawn

off

some

of

the

dog work on other machines, leaving your Alto free to do the interesting stuff. That's

why

we

have

a number

of

machines generically called

servers.

Nonnally, servers have special purpose, expensive

hardware attached to them (e.g., large-capacity disks, printers), and their sole purpose in life

is

to

make that hardware . available

to

more than one person/ Alto.

We

tend

to

identify servers by

function,

so

we

talk about printing servers,

file

servers, name lookup servers, mailbox servers, tape

servers, and so on. Many

of

the protocols for use

of

the Ethernet were developed precisely so that

personal Altos could communicate effectively with server Altos.

Printer servers and file servers get the biggest workout. There

is

considerable history and folklore

surrounding printing and printing servers--you

will

find some

of

it in later sections

of

this

document. One doesn't tend

to

hear much about

file

servers, except when they are down; nevertheless,

they are essential to our computational well-being. Because Alto disks are rather small (another

topic we'll come back

to

later),

we

rely heavily on

file

servers to store libraries

of

Alto packages,

subsystems, and documentation. In Palo Alto, our primary

file

servers are Maxc and two IFS servers,

Ivy

and

Iris.

A

file

server also acts

as

the natural common repository for the "truth version"

of

a system

being constructed by a number

of

individuals. And

file

servers are important to single individuals

since they provide greater capacity and higher reliability than local disks.

Alto

software

The first high-level programming language used

on

the Alto

was

BCPL, and quite a bit

of

program

writing

was

done in that environment. But BCPL

is

now a dead environment.

It

will be around

for some time to come, since there are BCPL programs that perform valuable functions for which

The Alto-Dolphin-Dorado Briefing Blurb 8

there are no current replacements: the printing server programs Press and Spruce are two

important examples.

Ot11er

languages that run on our computers are: Smalltalk

[18]

(an integrated,

interactive, object-oriented programming system), Mesa

[19]

(a strongly-typed, PASCAL-like

implementation language), Poplar (a simple, interactive, text-oriented language), a dialect

of

I nterlisp , and others. Mesa

is

perhaps the most widely used, with Smalltalk and Lisp coming in

second and third. Mesa

was

given a big boost in CSL when a variant

of

Mesa (itself called Cedar)

was

chosen

as

the base language for the Cedar programming environment.

There

is

a reasonable amount

of

introductory documentation for systems you commonly need (e.g.,

Bravo,

FfP,

the Alto Executive) in

[13].

This

is

by far the most useful single reference for the Alto

environment. Since the entire document can't be reprinted when any subsystem changes, however,

you can expect the information there to be somewhat out

of

date at

anyone

time.

If

you

suspect

you

need the latest documentation

for

some program

X,

you

might

try

[Maxc]<AltoDocs)X.press (or x.tty, or X-news.press).

The Alto Operating System

BCPL programs typically run on top

of

the Alto Operating System, which

is

itself written in BCPL.

Like most

ass,

this one provides a number

of

basic facilities, not all

of

which are needed by any

one program. Because the small memory

of

the Alto

is

precious, a technique called "Junta" exists

which permits BCPL programs

to

get rid

of

unneeded portions

of

the

as

during their execution.

"Counter-Junta" brings them back. You can read about the layers

of

the

as

in

{8}.

Mesa programs do not use the Alto

as

at all, mostly because Mesa and BCPL have rather different

philosophies about the run-time world in which they exist.

So

the first thing that a Mesa program

does when running on an Alto

is

to Junta away almost all

of

the

as,

and set about building a

separate Mesa world.

It

is

a considerable nuisance for Mesa and BCPL programs to communicate,

since their underlying instruction sets are completely different. So, most

of

the important

as

facilities (e.g., the

file

system) have been (re-)implemented directly in Mesa. Mesa's memory

management strategies replace the revolutionary tactics

of

"Junta" and "Counter-junta" with the

(relative) anarchy

of

segment swapping.

There is a program called the Executive which runs on top

of

the

as

and provides a command

interpreter with a number

of

natural facilities, such

as

"tell me what files are

on

this disk"

,"run

this

program", "execute this command file", "go away". System maintainers

will

tell

you

that the Executive

is

"just another

program-if

you

don't

like

it,

you

can

write

one yourself'. That's

true-you

could also write a Mesa

compiler yourself, but

....

In

all

fairness,

however, the Executive

is

one

of a number

of

programs that have reached the

state where maintenance

consists

of

aggravating details. Consequently, requests

for

feature enhancement are not likely to

fall

upon receptive

ears.

Perhaps the most useful features

of

the Executive are

file

name completion

(ESC) and *-expansion, particularly in conjunction with subsystem invocation. You should also

read about control-X and control-U in the Executive section

of

{IO}. Also, check

out

keyi.cm for

i=

1,

2,

and

3.

No

matter what program you are running, there are times when you want to say "get me

out

of

this

mess and back to somewhere more comfortable!" Unless things are

really

messed up, you have two

choices, both

of

which require you to know where the Swat key

is.

(This invaluable key is

unlabelled! On most keyboards,

it

is

at

the extreme lower right, next to the shift key; on

ADL

keyboards (in

case

you

ever find one), it

is

at the extreme

upper

right, separated somewhat from the

main keyboard area.)

By

hitting shift-Swat, you can normally get back to the

Executive-note

that

you must use the left-hand shift key to type "shift-swat", not the right hand one: the right

hand

one

is

too close to Swat itself for comfort. Control-shift-Swat

will

normally get you into Swat (the

BCPL debugger). What you do there

is

your own business (see {IO}). Control-Swat

will

get you to the

The Alto-Dolphin-Dorado Briefing Blurb 9

Mesa dcbugger

if

you are

in

a Mesa program, and there

is

a Mesa debugger on your

disk,

and it

is

installed, and your

core image isn't too badly screwed up.

If

you

are just trying to abort whatcver program

you

are running, you

probably don't want to be in the debugger

anyway.

If

these last-ditch facilities don't seem to work, things

are very confused, and you will have to boot your Alto, using the little white button that

is

not

only

unlabelled,

but

hidden behind the keyboard.

Pilot

The folks in SDD have produced a new operating system, written in Mesa, called Pilot. Pilot does

not run on Altos,

but

it does run on D-machines such as Dolphins

and

Dorados. Furthermore, by

running Pilot

on

your D-machine you get

aU

the advantages

of

virtual memory

and

multiprocessing,

which you

don't

get while pretending that you're running on an Alto.

Note

that there are currently

two different systems that someone can be talking about when they say "Mesa": Alto Mesa

and

Pilot Mesa.

The

Network Executive

There are several facilities available over the Ethernet that do not require a disk. You can boot any

one

of

these programs into your Alto by pressing down a strange collection

of

keys simultaneously

and hitting the boot button,

but

there

is

an

easier way.

If

you hold down the

BS

and'

(single

quote) keys and hit the boot button, you get the NetExec, a simple executive to which you can type

the name

of

the program you want to boot into your machine. Typing "?" will tell you what is

available.

If

you type the name

of

a program that should exist, and the screen flashes in discontent, it just means that

you

had the bad luck to contact a boot server without the complete set of programs.

If

you just type carriage return

again, the NetExec

will

try

to talk to a different boot server, and that might cure the problem.

The

most frequently

used facilities are the Scavenger, Chat, CopyDisk, and FTP. You can also get a variety

of

diagnostic programs, the most popular being DMT. And you can get an assortment

of

games.

Warning: many

of

the games use special Alto microcode, and hence

will

not run on Dolphins and Dorados.

It

is a little known fact that typing shift-swat to DMT

will

boot the NetExec. Then, typing "BootDPO" to the NetExec

will

boot your machine. And typing "NetExec" to the standard Alto Executive

will

boot the NetExec. Knowing all this,

you can manage to avoid hitting the actual physical boot button almost entirely,

if

such should be your

wish.

The Alto-Dolphin-Dorado Briefing Blurb

10

The

Alto file

system

Most general-purpose computer systems have some sort

of

file

system, and no

two

of

them are

exactly alike. Programmers tend to assimilate the assumptions

of

their local

file

system

so

completely that they forget that other systems do things differently.

As

a result, they sometimes get

burned when they start programming under a different system. Let's consider some

of

the implicit

assumptions behind the Alto

file

system organization.

Alto disks are self-contained. Exception: there exist Altos with

two

disk

drives that can be configured to spread

the

file

system across both

disks,

as mentioned above. Each one has a single directory in which the visible

names

of

the

files

are stored. Fine point: multiple directories are permitted, but most software can't handle them.

Names consist

of

a

file

name proper, optionally followed

by

a period and an extension. Actually,

file

names are terminated

by

a "." and

may

contain

any

number of embedded "."s. Dividing the name into

two

parts with a

single "."

is

purely a convention, though a widely-observed

one.

Certain conventional extensions exist, e.g.,

".mesa" for Mesa source programs.

All

of

this

is

probably familiar to

you

from other systems.

Wrinkle #

1:

The Alto

file

system supports version numbers that are essentially the same

as

those

of

TENEX

[9],

but almost no one uses them.

If

you are thinking about using

version numbers, don't. There are some lurking bugs in the Alto as related

to

version-

numbered

files.

Wrinkle

#2:

Because multiple versions are impractical, writing a "new version"

of

a file

really means writing on top

of

the old one. Nearly everyone who isn't accustomed to this

(particularly

PDP-IO

hackers) gets burned

by

it at least once. (However, there is an

important exception: Bravo maintains explicit backup

files

even when version numbers

are disabled.)

Wrinkle

#3:

Alto

files

consist

of

pages. Each page carries with it the number

of

significant bytes it contains. Thus,

in

principle,

a

file

need not be a sequence

of

full

pages followed by

a single partially

full

page.

In

jact, however, strange things will happen

if

you manage

to

construct a file in

which any page (except the last one)

is

not

full.

Fortunately,

it

is

hard to do

so.

Wrinkle #

4:

Alto files always have a page at the front called a

leader

page, which holds

various interesting and useful data about the

file

(e.g., when it

was

last written). For no

good reason, the Alto

file

system prefers that the

last

page

of

the

file

contain less than

512

bytes

of

data. This means that a logically empty

file

actually takes

two

pages, one for

the leader and one containing 0 significant bytes

of

data.

Wrinkle

#5:

The Alto disk architecture permits a representation for

files

that drastically

reduces the possibility

of

a hardware

or

software error destroying the disk's contents. The

basic idea

is

that

you

must tell the disk not only the address

of

the sector you want to

read/write, but also what you think that sector holds. This

is

implemented by dividing

every sector into 3 parts: a header, a label, and a data field. Each field may be

independently read, written, or compared with memory during a single pass over the

sector. The Alto

file

system stuffs a unique identification

of

the disk block (consisting

of

a

file

serial number and the page number

of

the

file)

into the label field. Now, when the

software goes to write a sector, it typically

asks

the hardware

to

compare the header and

label fields against data in memory, and to abort the writing

of

the data field

if

the

compare

fails.

This makes it. pretty difficult, though not impossible, to write in the wrong

place. The label field also contains links (disk addresses)

to

the predecessor and successor blocks

of

the

file.

It happens that

if

the compare logic

of

the disk microcode sees a particular pattern in a memory word.

The

Alto-Dolphin-Dorado Briefing Blurb

it

omits

the

comparison

on

that

word

and

instead

overwrites

the

pattern

with

the

data

from

the

corresponding

disk

word.

Thus,

by

cleverly

arranging

the

memory

"image"

of

a

label

field

to

be

compared,

the

software

can

get

Hie

safety

check

on

the

block

identification

AND

obtain

the

disk

addresses

of

the

neighboring

blocks

in

the

same

operation.

Cute,

huh?

More information about the disk system

and

how the software exploits it may

be

found

in

{I}

and

the "Disks

and

BFS" section

of

{8}.

11

You should also know

about

the Scavenger, a program that rebuilds the file structure

(but

not

the

file

content)

of

an Alto disk. Despite the checks

and

balances

of

the file system, occasionally things get

smashed

or

lost.

When

they do, running the Scavenger is the best first attempt to recover them

(assuming

that

your

hardware

is

functioning

correctly;

running

the'

Scavenger

won't

help

much

and

could

hurt

if

it

is

really

your

disk

drive

or

Alto

hardware

that

is

busted).

The

Scavenger is available from the NetExec, so

even

if

your disk is so messed

up

that you

can't boot

it, help is available. You can read more

about

the Scavenger

and

what it can do in {10}

and

[13].

Big Fish

in

a Small

Pond-the

Alto disk

Lots

of

smart people have spent lots

of

time producing lots

of

nifty software for the Alto. Programs

to manipulate directories, programs to format documents, programs to make pictures

and

illustrations, programs to transfer files, disks,

and

messages around, programs to help you write

programs, programs to ... oops, you

just

ran

out

of

disk space.

We

all know that you

can't

have your cake

and

eat

it

too. With a small disk, you

can't

even have

it, most

of

the time. Most people are amazed to learn that

an

Alto disk will hold over 4800 pages

(actually,

4872

pages,

a

little

under

2.5

MBytes)-they rarely see one with more than a

few

hundred

available. You will quickly discover that Alto programmers spend a significant fraction

of

their day

switching disk packs

or

running

FrP.

Some

do

both.

Of

course,

users

of

shared

Dorado

partitions

have

to

use

FrP

or

its

equivalent

quite

a

bit

as

well,

but

for

different

reasons.

There's no real cure for this disease,

but

by being aware

of

what is costly in space, you can make the pain less acute. Let's see where the

space goes by "building a disk" from scratch, so to speak.

Naturally, there are a few things that you

just

can't

live without. You

must

have

an

Operating

System,

an

Executive,

and

a

number

of

files that go along with them. You also need the basic file

system machinery (the directory and the disk descriptor

so

you

can

allocate

disk

space).

You also should

have Swatee

and

probably Swat, though the latter isn't really essential. There are also a

number

of

small files that the as

and

the Executive expect to find

around-don't

try to get rid

of

them, they

will just come right back. Even

so,

a disk with

just

the

as,

Executive, Swatee, Swat,

and

friends

still has about 3900 pages free.

Next come the facilities you nearly always want:

FTP

and

Bravo.

FTP

can always

be

obtained

from the NetExec,

but

that takes a while

and

you use

it

frequently, so most people keep it

around

on the disk.

It

consumes

about

180 pages.

For

wizards

and

hackers,

there

is

a

version

of

FfP

hiding

inside

SYS.BOOT,

and

one

can

put

together

a

small

kludge

that

transfers

control

to

it

This

way

you

can

have

FfP

without

giving

up

the

full

180

pages

it

normally

needs.

Bravo is a good deal larger, weighing

in

at

about

650 pages

by the time you

count

all its related files

and

a font

or

two. With

FrP

and

Bravo, your disk is now

down to around 3000 free pages.

At this point, things begin to diverge, depending on your plans for the disk. As

an

example,

let's

consider a Non-Programmer's Disk. This

is

a disk designed mostly for producing memos

and

documents

and

contains lots

of

files appropriate for these tasks.

When

you

get

it,

it

has

about

1600

free

pages-a

comfortable amount,

but

quite a drop from 3000. Where

did

those pages go? Well,

The Alto-Dolphin-Dorado Briefing Blurb

12

first there are the forms-files containing templates

for

things

you

commonly produce, like memos,

letters,

etc.

The standard bunch only consumes about

40

pages-cheap. Then come the fonts

...

and disk space starts

to

disappear. Screen fonts (so that Bravo can display things) occupy about

100

pages,

and you should probably retain the standard bunch (on a Non-Programmer's disk, at least).

The real space hogs are subsystems you rarely use. Chat takes

130

pages, and unless you spend a

great deal

of

time talking

to

Maxc

(in which case you probably don't care about Alto disk space),

you might

as

well

get it from the NetExec when

you

need

it.

Markup and PressEdit occupy

another

210

pages, Draw takes

150

more. Unless

you

use these facilities regularly, you are wasting

300

pages. Neptune takes up some more, unless

you

feel

that you can get

by

with the standard

Executive

file

system commands. There

is

also an Executive command "FileStat" that

will

tell

you

how big

files

are.

Finally, a Non-Programmer's disk also has BravoBug and some sample documents and

illustrations, which together occupy about

100

pages. They

are

pure

fat-you

almost never use

them, and can retrieve them from appropriate servers when necessary.

Perhaps this tirade on disk space seems superfluous-after

all,

a Non-Programmer's disk

does

have

over

1600

free pages even with all this junk. True, but other disks are rarely so empty. Things get

particularly tight on Mesa disks, so it

is

useful to know just what can be deleted and what can't.

The preceding discussion gives you an introduction, but Mesa programmers have been known to

go

out much further on the limb in their quest for breathing space (e.g., deleting

Swat,

SYS.ERRORS, and

related

files

that are only needed

when

the Alto

is

trying to tell

you

about a weird error condition). The moral

is:

know

what's on your disk and

why

it's there. Delete

*$,

Scratch*, and *.scratch occasionally-it's

amazing what you find lying around.

In summary, then,

we

can categorize some commonly encountered files

as

follows: Files on the same

line

generally assume or require that their brothers and sisters exist

Essential

files:

Sys.boot SysDir DiskDescriptor Sysfont.al Swatee

Executive.run Com.cm Rem.cm User.cm

Highly desirable:

Sys.errors Swat

FTP.run FTP.log

Bravo.run Bravo.error Bravo.messages (and various scratch files)

Useful:

Empress.run Fonts. widths

Neptune.run

Laure1.run or l.aurel.Image on Mesa disks

various .al font files

Partitioning

up

the pie: Dolphin and

Dorado

disks

Users

of

Dolphins and Dorados don't have to worry quite

so

intently about disk space, since their

local disks are much bigger. In

fact,

it turns out that their local disks are

so

big· that the Alto as

cannot address the entire disk! Hence, when a Dolphin or Dorado

is

emulating an Alto, its local

disk is split up into separate worlds called partitions. Dolphins disks hold two partitions, while

Dorado disks hold

five;

and each partition is

22,736

Alto pages in length (Oh boy, space to burn! Or

so

it seems

for

a while

...

). What partition

you,

are currently accessing

is

determined by the contents

of

some registers that the disk microcode uses. There

is

a command. called "partition" in the Executive

The Alto-Dolphin-Dorado Briefing Blurb

13

and the NetExec that allows

you

to change the current partition.

When operating in the Pilot world, a disk pack

is

called a physical volume, and it

is

divided into

worlds called logical volumes. Pilot logical volumes can be bigger than a partition, and frequently

are.

Hook,

Line,

and Sinker

How do you reel in those big

fish

we've just been talking about? With

FfP.

After Bravo,

FrP

is

probably the most heavily used Alto subsystem,

so

it

is

well

worth your while to learn something

about its facilities. However, the documentation in

[13]

is

sufficiently old that you should read the

relevant section

of

{10}

instead. We'll touch on the high points here.

Full-blown

FrP

(there are half-blown versions) operates three windows on the Alto display,

of

which

two

are interesting. The so-called "user" window

is

where

you

conduct your

file

transactions

with another machine, often (but not necessarily) a'

file

server. The "Telnet" window provides you

with a stripped-down version

of

Chat, and

is

handy when you want to do something that just isn't

covered

by

the

file

transfer protocol. Most

of

the time, however, the user window

is

all you ever

look at (or through). There are commands

to

establish and destroy connections, to retrieve, store,

delete, and rename

files,

and to interrogate directory contents and storage resources.

Much

of

the flexibility

of

FrP

is

derived from its command line processor, which, in conjunction

with the Executive's

file

name completion and *-expansion, provides considerable flexibility and

power. With flexibility comes the ability to

screw

yourself with ease,

so

FTP implements a

few

checks that prevent

you

from doing stupid things, at least without confirmation. You should read

about the / A and

/)

switches remembering that, unless

you

can afford

to

maintain multiple

versions, once you write on an Alto file, it's gone.

Editing and

Producing

Documents

In

the outside world, document production systems are usually de-coupled from text editors. One

normally takes the text one wants to include in a document, wraps it in mysterious commands

understood by a document processor, feeds it to that processor, and puzzles over the resulting

jumble

of

characters, on the page. In short, one programs in the document processor's language

using conventional programming

tools-an

editor, a compiler, and sometimes even a debugger.

Programmers tend to think this

is

neat; after all, one can do anything with a sufficiently powerful

programming language. (Remember, Turing machines supply a sufficiently powerful programming language too.)

However, document processors

of

this sort frequently define bizarre and semantically complex

languages, and one soon discovers that all

of

the time goes into the edit/compile/debug cycle, not

careful prose composition.

Bravo

is

a modest step

away

from the programming paradigm for document production. A single

program provides the usual editing functions and a reasonable collection

of

formatting tools. You

can't program it

as

you

would a document "compiler", but

you

can get very tolerable results in far

less time. The secret

is

in the philosophy: what

you

see on the screen is what you get on paper.

You use the editing and formatting commands to produce

on

the screen the page layout you want.

Then, you tell Bravo to ship it to a printer server and presto! You have a hardcopy version

of

what

you

saw

on the screen. Sounds simple, right?

Of

course, it isn't quite that easy in practice. There are dozens

of

subtle points having to do with

The Alto-Dolphin-Dorado Briefing Blurb 14

fonts,

margins, tabs, headings, and on and on. Bravo

is

a success because most

of

these issues are

resolved more or less

by

fiat-someone has prepared a collection

of

configuration parameters (in

user. em) and a set

of

forms (on a Non-Programmer's disk and the MAXC <Forms> directory) that accommodate

99%

of

the document production you have

to

do. Most

of

the configuration options aren't even

documented,

so

it

is

hard to get enough rope to hang yourself.

If

you

feel

suicidal, there are always

wizards about who can answer your

every

question about Bravo esotcrica. 'fhe net effect

is

that you spend much

more time composing and much

less

time compiling.

No one believes Bravo

is

the ideal solution; indeed, it has a lot

of

shortcomings that become

evident

as

you begin

to

push on

it.

Nevertheless, it

is

a·

sufficiently large step forward that

you

will

wonder how you tolerated the old

way

of

doing things. (If this isn't obvious to you after reading

[12]

and

[13],

wait until you've used it for a

few

weeks.) You

will

also find that the availability

of

multiple fonts, paragraphing, automatic indentation, and other formatting facilities inside the text

editor leads

you

to make prettier programs

as

well.

It just isn't that much more work to create and

maintain attractive source text, and a simple set

of

formatting conventions can be a more potent

program documentation aid than comments (see

[11]

for some examples). There are some operational

annoyances with using Bravo formatting, however. The only program which can interpret Bravo formatting information

and produce corresponding hardcopy is Bravo itself, and it can only do

so

on one

file

at a time and rather slowly.

Empress

is

much faster, but can only handle pre-formatted Press

files

or simple text (e.g., a sequence

of

ASCII

characters). There

is

a Hardcopy subsystem that takes a list

of

files

and

feeds

them one-by-one to Bravo

for

hardcopying

(it

uses

a Bravo macro

[13]

to

eliminate manual intervention), but this

is

a kludge at best. Therefore, some people

feel

that Bravo formatting is just too much trouble and instead do it "by hand". They are a small minority.

When Bravo crashes

Like all text editors, Bravo breaks once in a while. There

is

nothing quite like the sinking feeling

you

get when a large number

of

your precious keystrokes gurgle

away

down the drain. When they

do, you probably have an instinctive response (conditioned by previous editors you have used) to

run the editor again

to

find out what state your file

is

in. Resist this impulse at all

costs-it

is

the

worst

thing you can do.

Bravo has a "replay" mechanism, meaning that it records all

of

its

actions in a file and

is

capable

of

replaying an editing session

(yes,

even one involving multiple files) from the beginning. However,

all replay information

is

thrown

away

when Bravo initializes unless you tell it that you wish to

replay the immediately preceding session.

If

Bravo crashes on you,

by

diving into Swat or

displaying "bootlights", your best bet

is

to re-boot your Alto,

use

FTP

to

obtain BravoBug (unless,

of

course, you already have it), refresh your memory about how replays work

[13],

then run

BravoBug. Bravo/r

is

not an acceptable substitute. despite a popular rumor to that effect! More

details are available in

[13].

The essential notion

is

that you must not run Bravo in the usual

way,

or you will forfeit your opportunity to do a replay.

Square Pegs

in

Rhombic

Holes-Alto

Mesa

For years BCPL

was

the only implementation language for the Alto. Naturally, a nice cozy

environment for BCPL programs (and programmers) gradually developed, and the cognoscenti could

guess how subsystems would behave in unusual cases because they knew that the programs operated

in this environment. Then, along came Mesa and the end

of

innocence. Mesa programs either

have to mimic the behavior

of

the BCPL environment in situations where they supply overlapping

function,

or

risk being branded "incompatible".

Okay,

so

that's a bit melodramatic. Nevertheless, Mesa

is

faced with the problem

of

adapting

to

an

The Alto-Dolphin-Dorado Briefing Blurb

15

environment that it finds

less

than ideal.

As

subsystems coded in Mesa begin

to

emerge, subtle

incompatibilities appear (e.g., Mesa's inability, at present,

to

support version-numbered

files).

Mesa's more modern approach to memory management (implicit segment swapping instead

of

explicit overlays) has the disadvantage

of

consuming considerably more disk space, largely because it

has become much easier

to

ignore the constraints imposed

by

the Alto's small primary memory.

Mesa

is

nevertheless the progratnming language for successors

to

the Alto. These machines have an

architecture designed

to

support Mesa comfortably, and BCPL

will

fade away now that these

machines have arrived on the scene. Alto Mesa

may

be likened to a size

12

foot in a size

11

shoe;

Pilot Mesa

is

(you

fill in the blank).

Smalltalk

[This section

was

contributed

by

John Shoch.]

Small

talk

is

both a programming language and a progratnming environment, developed by the

Learning Research Group with lots

of

help from other folks in CSL and SSL. The system has

always been intended

to

serve

as

both a powerful language for use

by

experienced programmers and

an

easy

language to be learned

by

children; some

of

the work

of

LRG has been aimed at testing

out these systems with kids.

As

a programming language, Smalltalk

is

an "object-oriented" system which provides a uniform

epistemology:

*

*

*

Every "object"

is

an "instance"

of

some "class".

The class definition describes the behavior

of

all its instances.

Objects communicate by sending messages.

(Geneologists

will

recognize major parts

of

Simula and Lisp in our bloodline, combined with traces

of

many other languages.)

But Smalltalk

is

more than just a language

design-it

is

a highly interactive, integrated system

which tries to merge together many functions that are often viewed

as

separate subsystems: writing

programs, editing text, drawing, real time animation, generation

of

music, and more. This view

meshes well with the notion

of

a small, single-user personal computer (the "Dynabook"). Currently,

a large project

is

under

way

to publish the details

of

Small talk

80,

and to make it available at a very

low level to outside manufacturers

of

small computers, in the hope

of

getting it out into the world

by that route.

There have been many different releases

of

Smalltalk, but there have been three principal designs

so

far:

1)

Small talk

72,

a fully interpreted version developed for the Alto, and used in some

of

the original work with kids.

2)

Smalltalk

76,

a newer version incorporating the design

of

a virtual Smalltalk machine, a

microcoded version

of

this on the Alto, a compiler to produce byte codes executed by

the virtual machine, and an object-oriented virtual memory (called OOZE) upon which

the whole thing sits.

3)

Smalltalk

80,

a still newer version, currently being implemented, with a Large Object

The Alto-Dolphin-Dorado Briefing Blurb

16

Oriented virtual Memory (called LOOM).

For more information, take a look at

[22]

and

[23].

The "Smalltalk

72

Manual"

is

now

both out

of

print and

out

of

date, but did provide lots

of

interesting examples and

discussion;

try

to

borrow a

copy

from

someone.

No

Computer Scientist

is

an

Island:

the Laurel

message

system

We rely very heavily on an electronic mail system. Since people spend much

of

the day at their

Altos, notices posted on a central bulletin board are not likely

to

be seen rapidly. Accordingly,

most announcements are broadcast (to expansive distribution lists) using our electronic mail system.

If

you don't check your messages once a day or

so,

you

will

soon find yourself out-of-touch (and

saddled with a mailbox

full

of

obsolete junk mail). And conversely,

if

you don't make moves to get

on the right distribution lists early, you may miss lots

of

interesting mail. This business

of

using the

message

system

for

rapid distribution

of

announcements

can

get out of . hand. One occasionally receives notices

of

the

form:

"meeting X

will

start in 2 minutes-all interested parties should attend".

We

also use the electronic mail system

as

a

way

of

recording the progress

of

working groups and

projects. Minutes

of

meetings, design documents, and related materials often pass

as

messages

among group members. A

file

in which a copy

of

each such message

is

retained becomes a

valuable archive

of

the project history and

is

quite painless to maintain. Many individuals keep

archival files

of

their messages

as

well.

In the bad old days, the only generally available facility for sending messages

was

a Maxc subsystem

called SNDMSG. A separate program, MSG,

was

commonly used to inspect and classify incoming

messages. Consequently, people

who

had no other reason

to

use Maxc were compelled to process

their mail there.

Our replacement for MSG

is

an Alto-based message system named Laurel; Laurel

is

the message

composing and examining program, while Grapevine

is

the distributed transport mechanism, a collection

of

server

machines that conspire to deliver mail. Because Laurel stores mail locally on the Alto disk and requires a

moderate amount

of

disk space (about

500

pages), most users find it necessary to dedicate a disk on

which they process all their mail.

If

you like

to

read your mail frequently and you don't have a

double-disk system, you find yourself switching disks a lot. The latest version

of

Laurel (Laurel

6)

has lots

of

fun

new

bells and whistles that are worth getting to

know:

check out the modeless editor, thought

by

many to be the

greatest thing since sliced bread, and

try

"Run"ning some ".laurel" programs in the bottom

window.

Now that Laurel 6

is

around,

you

can

get the facilities

of

Chat, Ftp, and the Alto Executive

all

without leaving the Laurel cocoon.

The

Alto-Dolphin-Dorado Briefing Blurb

17

A

Printing

Discussion

You might expect that Xerox Corporation might

be

more than a little interested in printing.

Indeed, we are so interested that we have created an array

of

printing facilities sufficient to confuse

any newcomer. Let's try to understand the basics.

First

of

all, there is an important difference between

copiers

and

printers.

A copier obtains its

input

by scanning a physical image in some way. A printer obtains its

input

image

in

digital form from

some external source, e.g.,

an

interface to

an

Alto.

There are a

lot

of

printing programs about: Press, Spruce, Empress. There are a

lot

of

printers

too: Dover, Sequoia, Versatec.

To

make matters worse. each

of

the

instances

of

each

of

these

printers has a name as well: Clover, Menlo. Lilac, Daisy. As you might expect,

not

all programs

can talk to all printers,

but

we're working

on

that (see axiom 2 below). Here are a

few

axioms

that

may help you reason logically about all this:

1)

There are no line printers around here. All

of

our

printers are built

on

top

of

Xerox

copier printing engines that have

been

lobotomized

and

brainwashed to understand the

babbling

of

an

Alto instead

of

an

optical

input

scanner.

2)

Press files are the Esperanto

of

documentation. Most printer servers

demand

that

the documents you send them

be

in Press file format. This means you have to convert

whatever you have

in

hand

(usually text) to Press format before a server will deign to

print it.

There

are several ways to

do

this.

3)

Press files are hairy. Some printer servers

don't

support the full generality available

in a Press file. Generally, however, such servers will simply ignore what they

can't

figure

out, so you can safely send them any Press file you

happen

to have.

4)

There is

an

extensive collection

of

standard fonts.

and

they are mostly

straightforward to use. Be prepared for a few surprises

if

you insist on building your

own. The most unpleasant surprise

is

that

you

have to be a wizard in order to print with your

new

font!

You

can't

use

a

new

font unless it

is

added

to

the font dictionary on your printer, and adding

fonts

to

dictionaries

is

a delicate operation: a sad state of affairs

in

anyone's estimation.

In

general,

if

you simply want to make a memo,

or

a listing

of

a program,

or

a copy

of

a

documentation file

that

someone has sent you, things are quite straightforward. Bravo's hardcopy

command

[13]

will take the file you are editing, convert it to Press format

(induding

all the

formatting information you have supplied),

and

ship

it directly

to

any printing server you specify.

The

important server program to know about is Spruce, which understands everything Bravo can

produce. Spruce is the current driving program

of

choice for Dovers

and

Penguins,

and

is

the

server you will use for almost everything unless you are a graphics hacker.

Spruce will accept Press files from any source (though it does

not

implement all Press features).

Standard documents

and

memos are typically stored in Press format, so you can ship

them

directly

to your favorite Spruce server.

From

an Alto, use the Empress program; from Maxc

or

an

IFS, use

the PRESS command.

Empress can tell the difference between a Press file

and

a text file,

and

will convert a text file

to

Press format

if

necessary before sending

it

to the printing server.

If

you

do

this a lot, you will want

The Alto-Dolphin-Dorado Briefing Blurb

18

to

know about various options that apply to this conversion-see {10}. In such

cases,

Empress uses a

single font, which generally

has

a

fixed

pitch. This

is

the

way

we

simulate a line printer.

Spruce servers have a collection

of

fonts stored locally. Press

files

do not contain the representation

of

the fonts they require, only their names. Naturally,

if

a Press

file

is

produced using fonts that a

Spluce server doesn't have, the server

will

have a hard time printing

it.

Spruce

will

attempt a

reasonable substitution for unavailable fonts, and tell

you

about it on the break page

of

your listing.

If

you have chronic font difficulties

of

this sort, contact your local Spruce maintainer.

Most

frequently traveled paths through the printing maze

Running

on

Inpu t file Output

Program

format

desired

to

use

Maxc . Text Press file/printer PRESS command

Press Press printer PRESS command

IFS Press Press printer Press command

Alto Text Press file/printer Empress, Bravo

Bravo Press file/printer Bravo

Press Press printer Empress

Draw Press file Draw or ReDraw

SIL Press file SIL

A

few

caveats

go

along with this table. First, it

is

typically easier to format and print large files

frOln

Maxc (because

of

disk space considerations) than from an Alto, but it often takes longer.

Second, you should

know

that these various programs have a large number

of

options and defaults,

and they. are not

always

consistent. Beware

of

printing groups

of

files

with *-expansion on Maxc

(particularly

*.*)

unless you are certain

you

are doing it properly. (LIST

*.*

is

a

disaster,

for more

reasons than

you

might think.) For more details about printing, and before you try

to

do anything

clever, read {21}.

Beyond

the Black

and

White Horizon·

MAXC

and

the

Arpanet

Sitting at your Alto,

you

can easily forget about the other computing facilities that are within your

grasp. One important server on the network

is

MAXC, which

is

a home-grown microprogrammed

processor masquerading

as

a PDP-IO, and running Tenex.

Maxc

is connected

to

the Arpanet, so it

is

possible for

you

to reach out

to

any machine connected to the Arpanet, at least in principle. In

practice, not many people do (and there are restrictions imposed

by

our ARPA contract

as

well), except to

send messages

to

people at other Arpanet sites. Laurel understands Arpanet names in messages, so

you don't need

to

use

Maxc directly to send or receive Arpanet mail.

Looking

under

Rocks

All

Alto users should know about various interesting files and directories. There

is

no coherent

logic to the placement

of

"general interesf'

files

and directories, nor even to the division between

Maxc and Ivy.

Browse

through the glossary at the end

of

this document to get a rough idea

of

what's around.

If

something is available to the universities in the University Grant program, then

it

is

probably on

The Alto-Dolphin-Dorado Briefing Blurb

19

Maxc

(or archived off

of

Max

c),

since Maxc

is

the machine that the university

folk

can

access.

Browsing

on Maxc

The primary directories for documentation on Maxc are <AltoDocs>, (Doc>, (PrintingDocs>,

<Mesa-Doc>.

As

you

can see, the naming conventions aren't

very

consistent, so you may have to

fumble around a bit before you find the right one. The Tenex

file

name completer (ESC) can take

some

of

the difficulty out

of

remembering,

as

can a quick glance in the glossary at the end

of

this

document

Just because you don't find a particular file,

don

'(

give up! Tenex has an automatic facility called

"archiving", which moves infrequently accessed

files

to tape.

It

sometimes happens that the

documentation

you

are looking for has been archived. There

is

a Tenex command, "Interrogate",

that

will

help you locate an archived

file-see

[9].

Maxc

is

still the

file

repository

"of

record" for some families

of

files,

though that burden

is

gradually being shifted

to

various IFS servers. These servers frequently have duplicate copies

of

documentation, packages, subsystems, and the like. This

is

done partly

for

redundancy and partly to decrease

the load on Maxc when a

new

version

of

a popular Alto

facility

is

released. Duplicated directories always have

the same name on IFS servers, but are not always scrupulously maintained, and therefore may be

inconsistent, incomplete, or obsolete. Proceed with caution.

Browsing on IFS servers

IFS servers don't have an archiving facility (yet, although they may soon), which means that you are

less likely

to

overlook something interesting. IFS supplies a general sub-directory stnlcture which

the Maxc

file

system lacks, and

as

a result there are many more pigeonholes in which to look. For

example, on

Maxc

you might look for

<AltoDocs>My FavoritePackage.press

while on IFS

you

would probably look for

(Packages>

Doc>

MyFavoritePackage.press

(Packages>

My

FavoritePackage>Documentation.press

or perhaps some other permutation. This requires a bit

of

creativity and a little practice. However,

if

you use the "Chat Executive" and get in the habit

of

using "*"s in

file

name specifications, you

will

find all sorts

of

things you might not otherwise locate. Note that a "*,, in a request to an IFS

will expand into all possible sequences

of

characters, including right angle brackets and periods.

Thus, for example, a request for

(Packages>*press

refers to all

files

on all subdirectories

of

the Packages directory that end with the characters "press".

A "*,, won't match a left angle bracket,

by

the

way.

Thus,

if

you

ask

for "*.press", you are referring to all Press

files

on the current directory.

If

you

ask

for

"<*.press",

you

are referring to all

of

the Press

files

on the entire IFS (and

expect such searches to take a LONG TIME!).

Warning: Once you have gotten used to the IFS conventions about "*"s in

file

names, you will

find the TENEX rules quite restrictive and unnatural.

On

TENEX, an asterisk can only

be

used to

The Alto-Dolphin-Dorado Briefing Blurb

20

wildcard either the entire filename

or

the entire extension.

If

you

want

to

refer to

all

of

the files on

a TENEX directory,

you

must

say

"*.

*", not just

"*";

this lack

of

"forward compatibility" (the

opposite

of

backward compatibility?) has tripped up many a searcher.

Code

Phrases

You may occasionally hear the following incomprehensible phrases used in discussions, sometimes

accompanied by laughter. To keep you from feeling left out,

we

offer the following translations:

"Committing error 33"

(1)

Predicating one research effort on. the success

of

another. (2) Allowing your own

research effort

to

be placed on the critical path

of

some other project (be it a research

effort or not).

Known

elsewhere

as

Forgie's principle.

"You can tell the pioneers by the arrows

in

their backs."

Mostly self-explanatory. Usually applied

to

the bold souls who attempt to use brand-new

software systems, or to use older software systems in clever, novel, and therefore

unanticipated

ways

...

with predictable consequences.

Also

heard with "asses" replacing "backs".

UWe're

having a printing discussion. "

Refers to a protracted, low-level, time-consuming, generally pointless discussion

of

something peripherally interesting to

all.

Historically, printing discussions

were

of far greater

importance than

they

are

now.

You

can

see

why

when

you

consider that printing used to be done by

carrying magnetic tapes

from

Maxc

to a

Nova

that

ran

an XGP.

Fontology

The body

of

knowledge dealing with the construction and use

of

new fonts. It has been said

that

fontology

recapitulates

file-ogeny.

UWhat

you see

is

what you get."

Used specifically

in

reference to the treatment

of

visual images by various systems, e.g., a

Bravo screen display should be as close

as

possible

to

the hardcopy version

of

the same

text.

UH

ey

guys,

up-level!"

The conversation has degenerated to a discussion

of

nitty-gritty details. This phrase

is

often preceded or followed by: "We're having a printing discussion."

smashed

to

zero

A quaint

way

of

saying that some memory location has acquired the value zero when it

should have something else. "Smashed"

is

much preferred

to

"clobbered" in

local

argot, though in this

context it

seems

about

as

appropriate

as

using a

wrecking

ball to stack bricks.

ULife

is

hard"

Two possible interpretations: (1)

~While

your.

suggestion may have some merit, I will

behave

as

though I hadn't heard

it."

(2)

~Whi1e

your suggestion has obvious merit,

equally obvious circumstances prevent it from being seriously considered." The charm

of

this

phrase lies precisely in this subtle but important ambiguity.

The Alto-Dolphin-Dorado Briefing Blurb

"What's a spline?"

"Y

ou

have just used a term that I've heard for a year and a half, and I feel I should

know, but don't.

My

curiosity has finally overcome

my

guilt." Moral: don't hesitate to

ask

questions, even

if

they

SeelTI

obvious.

Some

CSL

Lore

Here are a

few

bits

of

information specific to CSL that you should know:

21

CSL has a

weekly

meeting on Wednesday afternoons called Dealer, starting at 1:15. The name

comes from the concept

of

"dealer's

choice"-the

dealer sets the ground rules and topic(s) for

discussion. When someone

says

she

will

"give a Dealer on X", she means that she will discuss X at

some future weekly meeting, taking about

15

minutes to

do

so

(plus whatever discussion

is

generated). Generally, such discussions are informal, and presentations

of

half-baked ideas are

encouraged. The topic under discussion may be long-range, ill-formed, controversial, or all

of

the

above. Comments from the audience are encouraged, indeed, provoked. More formal presentations occur

at the Computing Forum on Thursday afternoons, which is not specifically a CSL function and

is

open to all Xerox

employees. Dealers are also used for announcements which are not appropriate for distribution

by

electronic mail. Members

of

CSL are expected

to

make a serious effort to attend Dealer.

On occasions

of

great festivity, Dealer

is

replaced by a picnic on the hill (that

is,

Coyote Hill), with

Mother Xerox picking up the tab.

The CSL Archives (not to be confused with TENEX archives) are a collection

of

file

cabinets and

3-ring binders that provide a continuing record

of

CSL technical activities. The archives are our

primary line

of

defense in legal matters pertaining

to

our projects, but they make interesting reading

for anyone curious about the history

of

any particular project. You

will

find it most informative

to

browse the archives from time

to

time, just

to

see what's been going on in those projects you just

haven't quite had the time to monitor.

Ask

someone

to

point

you

at the cubicle where the archives

are stored.

If

you

are a CSL member and need a

new

disk pack, see Mike Overton in the CSL lab (across from

the Commons).

Some

ISL

Lore

Here

is

one item

of

information specific to

ISL:

ISL also has a weekly meeting, on Tuesday's starting at 11:00 am. This meeting is still nameless.

In

fact,

Chuck Geschke has a standing offer

of

a bottle

of

fine

Cabernet to anyone that can come

up with a name for this meeting that Chuck likes enough

to

adopt: the Cabernet

is

aging

unclaimed

as

of

this writing.

The Alto-Dolphin-Dorado Briefing Blurb

22

Gracious

Living

Hints

There are a couple

of

areas where life at PARe can be made more pleasant

if

everyone

is

polite

and thoughtful enough to

go

to some effort

to

help out. Here are a

few

words to the

wise:

Coffee

Both ISL and CSL have coffee alcoves where tea, cocoa, and several kinds

of

coffee are available.

All

coffee drinkers (not just the secretaries or some other such barbarism) help out

by

making

coffee.

If

you

are about to consume enough coffee that

-you

would leave less than a

full

cup in the

pot, it

is

your responsibility to make a fresh pot, following the posted instructions. There are lots

of

coffee fanatics around, and they get irritated beyond all reason

if

the coffee situation isn't working

out smoothly. For those coffees for which beans are

freshly

ground, the

local

custom

is

to pipeline grinding and

brewing;

you

are expected to grind a cup

of

beans

while

brewing a pot of coffee

from

the previous load

of

ground

beans. This speeds up the brewing process

for

everyone, since a load

of

ground beans

is

always

ready when the coffee

pot runs

out

Sharing Office Space

Be

warned

as

well

that some lab members are unbelievably picky about the state

of

their offices.

The convention

is

that any Alto in an empty office

is

fair game

to

be borrowed; Dolphins and Dorados

are another matter, because of the problems

of

sharing

disk

space.

But,

if

you borrow someone's Alto, or use

their office for some other reason, take care to put everything back exactly the way it

was.

Don't

spill crumbs around, or leave your half-empty cocoa cup on the desk, or forget

to

put

the owner's

disks back in her machine, or whatever.

Of

course, lots

of

people wouldn't mind even

if

you were

less than fanatically careful. But some people do mind, and there

is

no point in irritating people

unnecessarily.

Sharing

Dorados,

and Sharing Local Disk Space

The sharing

of

disk space has its own ethics and morality. First

of

all, don't attempt to "share" a

private partition, except with the explicit prior consent

of

the owner; only public partitions are

intended

to

be generally used in shared mode. The

law

regarding public partitions

is

that everyone

is

supposed to be living cleanly: that

is,

completely backed up on remote

file

servers. Hence,

according to the "letter

of

the law",

you

are completely within your rights

if

you delete anything

from a public partition, whether you really need more space

or

not. And in

fact,

even

if

the

"thing" that you are deleting

is

a standard system facility, such

as

the Mesa compiler. But going

along with the "letter

of

the law"

is

the

~'spirit

of

the law". We can all use public partitions more

effectively and spend less time in CopyDisk and FTP

if

we

treat the public partitions with some

care. Try not

to

delete standard systems, unless you really need the space. And

be

even more

careful not to leave non-standard versions

of

standard files on a public partition, where they might

confuse the user who

follows

you. Clean up after yourself

if

that

is

convenient, to give the next

user a pleasant start at her Dorado time.

In general, be aware that it

is

only good citizenship to

try

to

get a sense

of

the common Dorado

usage patterns in your environment, and not

to

upset those patterns when there are clear

alternatives. Oh

boy,

do I

feel

old!

When I first started hanging around

CSL,

the term "citizenship" referred to a

score computed

from

the timing and extent

of

one's usage

of

cycles

on

Maxc.

And a big. list giving everyone's

citizenship rating

as

well

of lots

of

other Maxc statistics

was

posted each month near the coffee alcove. Nowadays, right

across

the hall,

you

will

find the sign-up lists

for

the pool Dorados of CSL and

ISL.

Right next to the lists, you

will

find posted a full list

of

the current rules governing signing up, and a map showing the locations

of

the Dorado

The Alto-Dolphin-Dorado Briefing Blurb.

23

terminals.

Sharing printers

When

you

pick up your output from a printer, it

is

considered antisocial merely

to

lift your pages

off the top

of

the output hopper, and leave the rest there. Take a moment to sort the output into

the labelled bins. Sorting output

is

the responsibility

of

everyone who prints, just

as

making coffee

is

the responsibility

of

everyone

who

drinks (coffee). Check carefully

to

make sure that you catch

every break page: short outputs have a

way

of

going unnoticed, and hence being missorted,

especially when they are right underneath a long output in the stack. The rule for determining

which bin

is

to use the first letter that appears in the name on the break page. Thus, "Ramshaw,

Lyle" should be sorted under "R", while "Lyle Ramshaw" should be sorted under "L". A trickier

question

is

what to

do

with output

for

"Nonanle", which

is

the name of someone

who

hasn't logged in to their Dorado

partition. Following the rule would suggest

filing

such output under "N", but that doesn't

seem

very

helpful, since the

originator probably won't find

it.

Check the contents and

file

it in the right

box

if

you

happen to recognize

whose

output it

is;

otherwise, (?)

leave

it

on

top

of

Clover, or

(7)

stick

it back in the output hopper.

The

phone

system

If

you make a significant number

of

personal long-distance phone calls

off

of

Xerox phones, it

is

your responsibility to arrange to reimburse Xerox for them. This may not be that

easy,

either, since

phone bills take quite a while

(six

weeks

or

so)

to percolate through the bureaucracy upstairs, and the

said bureaucracy also has a lot

of

trouble figuring out where to send the phone bills

of

new people,

and people

who

move around a lot. Just because it

is

easy

to

steal phone service from Xerox

doesn't make it moral:

if

you think

you

aren't being paid enough, you should start agitating for a

raise. Furthermore,

if

enough suspicious

calls

are made without restitution, PARe (being a bureaucracy)

will

impose

some

bureaucratic "solution" on

us

all.

But enough

of

preaching:

so

as

not

to

end on a sour note, let's finish up by discussing how the

phone system works, anyway. The offices within

PARe

have four-digit extensions within the 494

exchange (what Ma

Bell

calls Centrex);

to

dial another office, those four digits suffice. Dialing a

single 9

as

the first digit gives

you

an outside line, and you are

now

a normal customer

of

Ma

Bell:

see a phone book [Oh, come

now,

surely

you

know

about phone books!] for more details. Dialing a single 8

gives

you different sounding dial tone, and puts you onto the IntelNet (not

to

be confused with the

InterNet,

of

course). The IntelNet

is

a Xerox-wide company phone system, complete with its own

phone book, and its own phone numbers.

If

you are calling someone in some remote part

of

Xerox, you can save Mother Xerox some bread by using the IntelNet instead

of

going straight out

over Ma Bell's lines. On the other hand,

you

may

not get

as

good a circuit to talk over; although this situation

is

said to be improving. Furthermore, through the wonders

of

modern electronics, you can dial any long-

distance number over the IntelNet. Just use the normal area code and Ma Bell number: the

circuitry

is

smart enough

to

take you

as

far

as

possible towards your destination along IntelNet

wires,

and then switch you over to Ma

Bell

lines for the rest

of

the trip. Using the IntelNet doesn't start

to

save

money until the

call

is

going a

fair

distance; therefore, the IntelNet doesn't let you

call

outside numbers in area

codes

408,

415,

and 916-better to just dial 9 and go

via

Ma

Bell

from the beginning.

One more thing: after you have dialed a number on the IntelNet, you will hear a funny little

beeping. At that point, you are being asked to key in a four-digit number

to

which the call should

be billed. You should use the four-digit extension number

for

your normal office phone under

most circumstances.

Calls

made

by

dialing 9 instead

of

8 are

always

charged

to

the phone from which they are

placed.

The Alto-Dolphin-Dorado Briefing Blurb

24

If

you are expecting a call

but

won't be near your normal phone, a call forwarding facility exists:

dial

106

and then the number to which you want your calls

to

be forwarded. Later on (try not to

forget), you dial

107

on your nonnal phone to cancel the forwarding. There

is

also a

way

to

transfer incoming calls to a different Xerox number: Depress the switch hook once, and dial the

destination number; when the destination answers,

you

will

talking to the destination

but

the

original caller won't be able

to

hear your conversation; depressing the switch hook again puts all

three

of

you on the line; then you can hang up when you please.

If

the destination doesn't answer,

depressing the switch hook a third time

will

flush the annoying ringing or busy signal.

The Alto-Dolphin-Dorado Briefing Blurb

25

ADL

keyboard

Adobe

Alpine

Alto

A

Glossary

of

Terms,

Subsystems,

Directories,

and

Files

(and

acronyms,

protocols,

and

other

trivia)

ADL

is

a acronym

for

the Advanced Development Laboratory, a part

of

PARC located in Southern California. This organization came up with the

ADL

keyboard

as

an inexpensive alternative to Microswitch keyboards, and

they were used on the first

few

builds

of

Alto II's. They have extra columns

of

function keys separated from the primary keys on both sides; the feel

of

an

ADL keyboard

is

unique.

A program for submitting, collecting, and managing AR's. Subsumes the

functionality

of

the former ARSubmit.

A project within CSL

to

build a transactional

file

server for use

by

data base

systems to be built within Cedar and the hypothetical Cedar universal file

system. A follow-on to Juniper.

If

you

don't know by

now

...

AltoFontGuide.Press A

file

that tells all about the existing families

of

display screen raster fonts,

and describes how they are organized

as

different subdirectories on

[Ivy]<AltoFonts>.

APC

AR

ARSubmit

ASD

bank

bar

Baybill

BCPL

In the armed forces, an acronym

for

Armored Personnel Carrier; used

to

refer

to

the massive cabinet designed tohousebreak a Dorado. No one seems

to

know what the acronym really stands for in the Dorado case: Armored

~ersonal

,Qomputer, or Armored rrocessor ,Qarrier are two possIbilities.

Acronym for Action Request: a report

of

a bug or a request for a new

feature. AR's are part

of

mechanism developed within SDD for handling

feedback from users

of

programs to their implementors. AR's are only

relevant for software produced

by

SDD.

Network-bootable program for submitting AR's (widely reviled).

Acronym for Advanced §ystems Department, which

was

once a part

of

XBS,

but

was

disbanded some time ago.

A unit

of

measurement

of

primary storage, equal to 64K 16-bits words, or

equivalently, 128K bytes. An Alto II has four banks, while Dorados have at

least eight.

A generally thin, generally rectangular, generally invisible region

of

the screen

in which certain generally display-related actions occur, e.g., the scroll bar,

the line-select bar.

Another name for Building

96,

occupied by part

of

SDD. The Bayhill

building is located on Hillview just before it runs into Arastradero.

A system programming language used

as

the basis for many Alto facilities.

Also,.

the compiler for that language.

The Alto-Dolphin-Dorado Briefing Blurb

26

BFS

BITBLT

bitmap

Boardwalk

boot

boot button

boot server

bootlights

Bravo.run

BravoBug.run

BravoX.run

bug

award

Building

32

Building

34

An

acronym for

Basic

File System; the contents

of

a disk or partition used

by

the

Alto

world. -

Also

a standard software package for low-level

management

of

an Alto

file

system.

(pronounced "bit-blit"). A complex Alto instruction used for moving and

possibly modifying a rectangular

bitmap.

The "BLT" part

is

an acronym for

BLock

Transfer.

Generally refers to a representation

of

a graphical entity

as

a sequence

of

bits

directly representing image intensity at the points

of

a raster. The Alto

display hardware and microcode process what

is

essentially a bitmap

of

the

image

to

be displayed. At PARC, bitmaps are normally stored in word-aligned, pure

row-major order.

Another name for

Building

35,

the main building

of

PARC

(mostly heard in the

conversation

of

residents

of

PARe-place).

Short for "bootstrap", which

is

in tum short for "bootstrap load". Refers to

the process

of

loading and starting a program on a machine whose main

memory has undefined contents.

The small button behind an Alto keyboard used (sometimes in conjunction

with the keyboard) to

boot

some program into execution. One

of

several

such small buttons on a

Dolphin

or

Dorado.

A computer on the network that provides a retrieval service for certain stand-

alone programs. See NetExec.

A screen pattern resembling a city skyline. Occurs occasionally when some

erroneous unanticipated condition arises, e.g., getting a parity en-or in a

BCPL program on a disk that doesn't have

Swat.

An integrated text editor and document formatting program that runs on the

Alto; a vital program that nevertheless

is

no longer maintained or supported.

A program used when Bravo crashes to

replay

the editing actions up to the

point

of

the crash,

and/or

to

report

the problem. (For some time, Bravo has been

receiving only such maintenance

as

is truly unavoidable, so ignore the reporting function.)

A successor to

Bravo

written in Butte with somewhat greater functionality

and a somewhat richer interface. Warning!: BravoX source files are stored in a weird

and wonderful format that almost

NO

programs other than BravoX can handle. Also, BravoX

runs,

at

the moment, only on Alto II's and (perhaps?) Dolphins.

Refers to a relatively recent custom within CSL and ISL, wherein those brave

souls responsible for ferreting out the cruelest and most intricate bugs in

critically important systems are rewarded for their efforts by being presented

with a cute little bug-shaped sticker that they can then display on their office

nameplate or elsewhere (the rough equivalent

of

a gold star).

A part

of

PARC,

located on llanover Street, north

of

Page Mill. Also called

PARC-place.

A part

of

PARC,

located on Hillview, just across Coyote Hill from the

Building

35,

the home

of

the

ICL.

The Alto-Dolphin-Dorado Briefing Blurb

27

Building

35

Building

37

Building

96

Butte

byte code

Cabernet

Cascade

Cedar

CedarGraphics

CenterPunch

Chardonnay

Chat

Chipmunk

Cholla

click

The main building

of

PARe, located at the intersection

of

Coyote Hill and

Hillview. The site

of

the cafeteria. Occasionally called Boardwalk (to

contrast it with PARe-place).

A part

of

PARe, located on Hanover Street, north

of

Page. Mill, and just

south

of

PARC-place. The site

of

the CSL Electronic Model Shop.

A part

of

OPD, located where Hillview runs into Arastradero; also called the

Bayhill building. Current home

of

some parts

of

SDD.

A new compiler for BCPL that outputs Mesa-style byte codes instead

of

Nova assembly code; also, the byte codes themselves, and the microcode that

implements them.

Lisp, Mesa, Smalltalk, and Butte at

PARC

compile into directly executable

languages that are stack oriented, and whose op codes are usually one byte

long. Such an instruction

is

called a byte code. These byte codes are in turn

interpreted

by

special microcode.

A particular Alto mail server that

is

part

of

the Grapevine distributed

transport mechanism, located in CSL.

See PreCascade.

A large project in CSL

to

build a programming environn1ent for essentially

all

of

CSL's future applications. Cedar

is

also the name

of

the programming

language upon which this Cedar system

is

built, a variant

of

Mesa augmented

by

garbage collection and run-time types. The design

of

the Cedar

environment

was

strongly influenced by the programming environment and

services in Interlisp.

A subroutine package

of

graphic primitives that forms an important part

of

Cedar. Its design

was

heavily influenced by the results

of

experimental

systems written in JaM.

An old name for Hornet.

An

Alto mail server that

is

part

of

the Grapevine distributed transport

mechanism.

A subsystem that permits teletype-like, interactive access to a remote

computer on the network. Used also to refer to a facility resembling that

provided

by

this subsystem, e.g.,

FTP

is

said to have a Chat window. Chat

is

mainly used to communicate with Maxc and IFS servers.

A D-machine program for interactively creating and editing integrated circuit

designs. Chipmunk makes use

of

a color display in addition to the normal

black-and-white one. It

is

a successor to Icarus.

A Laurel-based process control program being written for ICL with help

from

CS;L.

A manipulation

of

a mouse button. Pushing and releasing a mouse button

several times in quick succession is sometimes called a "double-click", "triple-

click", etc.

as

appropriate.

The Alto-Dolphin-Dorado Briefing Blurb

28

client

Clover

Clover

Fonts.Press

CoCo Pilot

Com.

em

config

CoPilot

Copy

Disk.run

CSL

CSL Notebook

D-machine

Daisy

Dandelion

dead

Dealer

DDS. run

DfFiles

A program (rather than a person) that avails itself

of

the services

of

another

pr?gram or system. Laurel

is

a client

of

Grapevine. See user.

A Dover located in CSL.

A

file

that lists

by

family

name,

face,

size,

and rotation all

of

the fonts in

Clover's font dictionary; available on [Ivy]<Fonts). To see the characters

themselves, check out the book located on top

of

Clover called

CloverCharacters.Press.

A

world-swap

debugger for CoPilot.

A

file

used

by

the Alto Executive to store the current command being

executed. See Rem.em.

A source

file

that tells the Mesa Binder how to assemble modules into a

complete system.

A

world-swap

debugger for Pilot.

A stand-alone program used

to

transfer a BFS, that

is,

the entire contents

of

a disk or partition.

May

be used between computers or on a single computer

with mUltiple disk drives.

Acronym for

~omputer

§cience 1aboratory, a part

of

the Systems Center

of

P

ARC,

located on the second floor

of

Building 35.

A mechanism for distributing, indexing, and generally sharing the

documentary output

of

folk

in CSL.

A supergeneric name, referring to any

of

the current machines within Xerox

that implement the PrincOps architecture: Dandelions, Dolphins, and

Dorados are the primary D-machines.

A Dover located in the Bayhill building.

The (former?) name

of

the processor that

is

in the

Star

products; an example

of

aD-machine.

Either not currently operational (said

of

a piece

of

hardware),

or

operational

but not currently undergoing continued development and support (said

of

bodies

of

software).

The name

of

CSL's weekly meeting, occurring on Wednesday afternoons

from 1:15 until 2:45

(or

so);

also used to refer to the person speaking at that

meeting. Giving such a presentation

is

referred

to

as

"giving a Dealer"

or

sometimes

"Dealing" .

Acronym for Descriptive Directory

~ystem.

An Alto subsystem providing

more sophisticated manipulation

of

the

file

system than

is

available with the

Executive.

See

also Neptune, which

is

a poor man's DDS: it provides most

of

the functionality but uses less disk space and time.

A collection

of

programs for describing and automatically retrieving

and

building complicated Mesa systems. Built by Eric Schmidt

as

a forerunner

of

real system models, DfFiles primarily addresses the problems engendered by

our current feudal and highly non-universal collection

of

file systems. See

The Alto-Dolphin-Dorado Briefing Blurb

29

dirtball

DiskDescriptor

DLISP

DLS

DMT.boot

DOC

Dolphin

Dorado

Dover

Dragon

Draw.run

Dumper.boot

DWIM

EARS

[Ivy](CedarLib)DfFiles)DfFiles.Bravo or ditto.Press.

A small, perhaps struggling outsider; not in the major or even the minor

leagues. For example, "Xerox

is

not a dirtball company". The author

is

uncertain to what degree this term

is

derogatory.

A

file

that contains the disk allocation information used by the Alto file

system.

A version

of

Interlisp running on Maxc that communicates with some fancy

display manipulation facilities on the Alto; largely supplanted and not

to

be

confused with Interlisp

D.

Acronym for Data

1ine

~canner:

an Alto equipped with lots

of

modems

plus other hardware and microcode to allow dialing into and out

of

the

Internet.

Acronym for Display Memory rester. A memory diagnostic for the Alto.

DMT

is

automatically booted from the network by the Alto Executive after

the Alto has been idle for about

20

minutes. DMT accepts various commands;

try

pushing the "S"

key,

and also

try

typing shift-swat. Designing cursors for DMT

is

a popular

sport: send your suggestion

as

a list

of

16 octal numbers to David

Boggs

(Boggs.PA), along

with a suggested title line and an indication of whether you want to be credited by name.

A Cedar concept and collection

of

programs for giving flexible active

views

of

various forms

of

structured data, text or otherwise. DOCs were once called

documents.

Generic name for a personal computer once called the

DO.

Generic name for a high-performance personal computer designed by CSL.

Generic name for a type

of

384

bpi laser-scan printer built on the Xerox

7000

xerographic engine and connected

to

an Alto by means

of

a Orbit

interface. Successor to EARS. Dovers are normally driven by Spruce.

Generic name

of

a new, custom-chip processor being designed by a team in

CSL; it

is

hoped that the Dragon

will

satisfy our ambitions to have

"a

Dorado in a shoe box",

An

Alto subsystem that permits interactive construction

of

pictures composed

of

lines, curves, and text; not a very solid system. Draw users may be interested

to note that a program ReDraw exists that converts Draw source files into

Press

files

that

will

print without the jaggies on a Dover.

A file used for desperation debugging. Dumps (most of) the current core

image to Swatee for subsequent inspection

by

a debugger.

Acronym for Do What ! Mean: a facility intended to make LISP do what

you mean, not what you say.

Acronym for gther

~lto

Research

~LOT.

An obsolete prototype laser-scan

printer built on the Xerox

·7000

xerographic engine and equipped with a

hardware character generator. (Interesting to some

as

an example

of

a third level

acronym: the S in EARS stands

for

SLOT, and the L in SLOT stands for LASER, and

LASER

itself

is

an acronym!)

The Alto-Dolphin-Dorado Briefing Blurb

30

Electronic Model Shop An arm

of

CSL located on Hanover street in Building 37; this group

of

folks

do

small-scale production runs of computer equipment for CSL.

Frequently called the Garage.

EmPress.run

EOS

Ernestine

Ethernet.

Executive.run

file

extension

An

Alto subsystem used

to

convert text

files

to Press format and ship them

to

a Press printer server.

Acronym for glectro-Qptical

~ystems;

a part

of

Xerox located in Pasadena.

An

Alto server that allows you to dial up and read your mail while it

is

sitting in your Grapevine mailbox; primarily useful when, due

to

travel

or

whatever, your personal computer and Laurel are unavailable.

The communication line connecting several Altos (or other computers with

compatible interfaces) together. Strictly speaking, an Ethernet

is

a single,

continuous piece

of

co-axial cable, but the term

is

sometimes applied to the

entire network accessible through the cooperation

of

Gateways (which

is

more correctly called an InterNet). Every Ethernet within an InterNet has a

unique identifying number. Ethernets come in two

flavors:

the original Ethernet, now

called the Experimental Ethernet,

was

built within PARC and runs at 3 MBits/sec. The

Ethernet that has been proposed

as

a communication standard

is

a re-engineering that runs at

10

MBits/sec.

All

of

the Ethernets currently within PARC are

of

the earlier, 3 MBits/sec

variety.

A distinguished Alto subsystem that provides simple commands to inspect

and manipulate the

file

system directory, and

to

initiate other subsystems.

The portion

of

a

file

name that appears following a period (possibly null).

By

convention, a number

of

extensions are reserved to indicate the type

of

data in the

file,

though not all subsystems are consistent in their defaulting

of

extensions.

Some commonly encountered extensions are:

al

bcd

bcpl

bfs

boot

br

bravo

cm

con

fig

df

dm

error(s)

image

ks

laurel

log

mail

mail-dmsTOC

mesa

press

run

sil

st

symbols

syms

an Executive command (not really an extenSion)

Alto screen font

Mesa object program module

BCPL source program module

an entire

file

system gathered into a

file

program invokable

by

booting

BCPL object program module

text file containing

Bravo

formatting information

Executive command

file

Mesa source that describes how to combine modules

description

of

a con

fig

including path names for files

dump

file

(Le.,

several logical files stored

as

one)

Swat error message

file

executable (Mesa) program

new

format Alto screen font

special flavor

of

.bcd that can be run within Laurel

history

of

certain program actions

Laurel mail

file

Laurel table-of-contents

file

Mesa source program module

Press file

executable (BCPL) program,

SIL source file for a drawing

Smalltalk source program text

Mesa symbol table (for debugging)

BCPL symbol table (for debugging)

The Alto-Dolphin-Dorado Briefing Blurb

31

file

server

FLG

fog

index

font

Fonts.widths

FTP.run

Garage

Gateway

Grapevine

Griffin

group

Guibas

Hardy

Hornet

tex

tfm

ts,

typescript

TEX source text

font metric information,

for

use with TEX

typescript

file

(log

of

interaction)

A computer on the network that provides a

file

storage and retrieval service.

MAXC,

IFS, and Juniper are three different types

of

file

servers, though

they provide related facilities.

(pronounced "flug

tt

).

A switch (usually

in

Lisp programs) that customizes a

program's behavior

to

an individual user's working habits.

A measure

of

prose obscurity. Units· are years

of

education required for

understanding.

An

assortment

of

characters all

of

one

size

and style; more precisely, a

mapping from a set

of

character codes

to

a consistent collection

of

graphic

images.

A

file

containing character-width information for a large number

of

fonts.

Used by many programs that do text formatting while producing Press

files.

The standard source

is

[Ivy)<Fonts)Fonts.Widths.

Acronym for

.Eile

Transfer rrotocol (or rrogram). An Alto program that

provides a convenient user interface to the file transfer protocol, enabling the

transfer

of

files

between co-operating computers on the Internet.

A nickname for the Electronic Model Shop, a part

of

CSL.

A computer serving

as

a forwarding link between separate Ethernets.

Gateways may also perform certain server functions, such

as

name lookup.

The distributed electronic message transport system; it has a set

of

protocols

all its

own,

and provides various server functions such

as

authentication.

A Mesa illustration program, a successor

to

Draw. Excellent on filled areas,

and handles color. Griffin

was

the source

of

many

of

the pretty pictures

hanging near Lilac.

(when referring to Grapevine) A set

of

R-names.· The standard

interpretation

of

a group

is

a distribution list. For example, CSLt.PA

is

the

group

of

all people in CSL, in case they all should get copies

of

a message.

Groups can also be used for other purposes, such

as

access control. The R-

names that constitute a group are called its

members.

In addition, a group has

friends

and

owners:

a friend

is

someone

who

may add or delete herself from

the group, while an

owner

may add or delete anyone from the group.

A unit

of

complexity

of

mathematical arguments, defined to be Leo's

maximum sustainable hair-level. For practical purposes, the milliGuibas is a

more reasonable unit.

A Tool that provides the functionality

of

Laurel in the PreCascade

environment: a client

of

Grapevine.

Generic name for a family

of

300

bpi laser-scanned printers, built on top

of

2600

copiers.

The Alto-Dolphin-Dorado Briefing Blurb

32

Ibis

Icarus

Idun

ICL

IFS

Igor

ISL

Inscripts

install

Interiisp

InterPress

Iris

Ivy

[Ivy]<AltoFonts>

[I

vy]<BasicDisks>

[Ivy]<

Cedar>

[Ivy)<CedarLib>

[Ivy]<Fonts>

An

IFS server

in

SDD/Palo Alto.

An

Alto-based program for creating and editing integrated circuit designs

graphically and interactively.

An

IFS server in SDD/Palo Alto: the home file server

of

the Pilot group.

Acronym

for

Integrated

~ircuit

1aboratory, a part

of

the Science Center

of

P

ARC,

located in Building 34.

Acronym for Interim File System. An Alto-based

file

server. Several distinct

IFS servers exist on various Ethernets, including

Ivy,

Ibis, Iris, Idun, Igor,

Phylum, XEOS, Erie, and about

15

others.

An

IFS server in SDD/Palo Alto: the home file server

of

the Mesa group.

This name should be pronounced "Eye-gore",

as

in the movie

Young

Frankenstein.

Acronym

for

Imaging §ciences 1aboratory, a part

of

the Systems Center

of

P

ARC,

and located on the second floor

of

Building 35.

A mechanism for keeping track

of

user input to a program in a general

way

(key strokes, mouse clicks, and the like), for use within Cedar.

A term applied to the Alto Operating System and a number

of

subsystems

(notably Bravo), referring

to

a procedure whereby certain configuration

options are established. Frequently, what

is

really

going

on

is

that the program being

installed

is

salting

away

somewhere the current hard

disk

addresses

of

the pages

of

important

files,

so

that later

access

to those

files

can avoid the tedious operations

of

looking up the

file

in

a directory and chaining through disk headers to get to the right place within the

file.

A dialect

of

Lisp with a large library

of

facilities and a IS-pound reference

manual. Interlisp D

is

a dialect

of

Interlisp that

is

being developed for use

on D-machines by people at P ARC-place.

A printing file format standard that

is

being developed: a second cut at the

same issues addressed by Press format

An

IFS server

in

SDD/Palo Alto, which serves

as

the official source

of

released Pilots.

An

IFS server in PARC, used

by

CSL and ISL.

A directory on which screen fonts for the Alto are stored (extension .AL).

Subdirectories are used on this directory to distinguish various families

of

display screen fonts that have accumulated over the years.

A directory on which the standard starting configurations for Alto disks are

stored,

as

files

with extension ".bfs". The normal

way

to initialize a new Alto

pack

is

to use

Copy

Disk

to

retrieve one

of

these disk images.

The source

of

actual Cedar. code and documentation.

A library

of

packages for use within Cedar.

A directory containing various documents

of

printing interest, including

Fonts.widths. You might be interested in CloverFonts.Press,

and/or

AltoF ontGuide.Press.

The Alto-Dolphin-Dorado Briefing Blurb

33

[Ivy]<Mesa>

[I

vy

]<MesaLib>

[Ivy]<Pilot> Doc>

[Ivy]<APilot>

jaggies

JaM

Juniper

Junta

Kanji

KBA

KRL

Lampson

Laurel

Leaf

level

i system

Librarian

Lilac

logical. volume

A directory on which Mesa programs (source and object) and documentation

are stored. Additional facilities

of

interest

to

Mesa programmers

may

also be

found on <MesaLib>.

A directory on which Mesa utilities and packages (source, object and

documentation) are stored. Standard Mesa programming facilities may be

found on <Mesa>.

The home

of

the memo SettingUpPilot.

A directory that

is

periodically reinitialized

as

a complete copy

of

[Idun]<APilot#O), where

"#"

is

the most recent pilot release (currently

#=6).

The annoying sharp corners visible when curves are imaged on a raster

device without sufficient resolution.

Acronym for

lohn

(Warnock)

~nd

Martin (Newell). An interactive language

with a simple, stack-oriented execution model and equipped with lots for

graphic operations

as

primitives; implemented in Mesa.

An Alto-based distributed

file

system, built within CSL.

A technique for eliminating layers

of

the Alto Operating System that are not

required by a particular subsystem.

A Dover in Building

34.

Acronym for

Know1edge-~ased

Assistance. Refers

to

a former project in

CSL.

Acronym for Knowledge Representation !:anguage. Refers to a former

project in CSL.

A unit

of

speech rate. 1 Lampson

is

defined

as

Butler's maximum sustained

speed. For practical applications, the milliLampson

is

a more appropriate

unit.

An Alto-based, display-oriented program that provides access

to

the facilities

of

Grapevine.

A page-level file access protocol supported by some IFS's.

(for i E

[1..3]).

A terminology for classifying (software) systems according to

their intended user community:

1 implementors only

2 implementors and friendly users

3 naive users

A Tajo program for check-in/check-out

of

the modules

of

a large Mesa

system, used in SDD; also, a server for this program.

A Puffin located in CSL, right next

to

Clover.

A portion

of

a physical volume that

is

being used to support a Pilot

environment: the Pilot equivalent

of

a partition.

The Alto-Dolphin-Dorado Briefing Blurb

34

LRG Acronym for 1earning .Research Group, a part

of

the Science Center

of

PARCo

Maggie A tape server; that

is,

a machine on the Internet with tape drives that it

will

let a requesting machine use.

Magic Acronym for Multiple Analyses

of

the Geometry

of

Integrated

~ircuits.

A

system for dealing with VLSI designs: printing them, converting them

among

fOlmats,

examining them with various programs.

MakeConfig A program that reads Mesa configs and

beds

and produces a collection

of

commands that

will

compile and bind the many modules

of

a system in the

correct manner

to

build a consistent system. For documentation, see

[I

vy

]<CedarLib> MakeConfig>MakeConfig.Press and ditto. bravo.

Marion A Librarian server in SDD/Palo Alto.

Markup.run A (dead) Alto subsystem for editing Press

files.

MAXC

Acronym for Multi-Access

~erox

~omputer

(pronounced "Max"). A locally

produced computer that

is

functionally similar to the DEC PDP-IO. At one

time, there were two MAXC's, named Maxcl and Maxc2, but Maxcl has

gone

away

forever. From now on, "Maxcl", "Maxc2", and "Maxc" are all

natnes for the same machine, which used to be called

Maxc2.

[Maxc]<Alto> A directory on which standard Alto (BCPL) programs and subsystems are

stored. Only object code files (extension .BR) and runnable

files

(extension

.R

UN) are stored here; source

files

and documentation are stored on

[Maxc]<AltoSource> and [Maxcl<AltoDocs>, respectively.

[Maxc]<AltoDocs> A directory on which documentation for Alto programs

is

stored. Common

extensions are .PRESS (for

files

directly printable by Press or Spruce), and

.TTY (plain text). See [Maxcl<AltoSource> and [Maxcl<Alto> for

corresponding source and object files.

[Maxc ]<AltoSource> A directory on which source versions

of

standard Alto programs are stored.

[Maxcl<Forms>

[Maxc]<Printing>

Corresponding object versions and documentation are stored on <Alto> and

<AltoDocs>, respectively.

A directory containing

files

that are usable

as

templates (in Bravo) for various

kinds

of

documents (e.g., memos, letters, reports).

A directory containing printing and graphics programs.

[Maxc]<PrintingDocs> A directory containing documentation related to printing and graphics

facilities such

as

Press files and font

file

formats.

[Maxc]<Secretary> A directory containing standard distribution lists for use with SNDMSG.

[Maxc]<SubSys> A directory containing standard TENEX subsystems.

Mokelumne A former release

of

Pilot.

Menlo A Dover located in ISL.

The Alto-Dolphin-Dorado Briefing Blurb

35

menu

Mesa

MesaNetExec

MetaFont

A collection

of

text strings or icons on a display screen generally used

to

represent a set

of

possible actions.

A PASCAL-like, strongly typed, system programming language developed

by

CSL and SDD.

A Mesa implementation

of

the NetExec; valuable because it knows how to

load Othello.

A font-designing language built by Don Knuth at Stanford, and used

to

generate fonts for use with TEX. Metafont

is

available

as

MF.Sav on Maxc.

Microswitch keyboard Microswitch

is

a company that make keyboards. The standard Alto

keyboard, also in use at P

ARC

on Dolphins and Dorados,

is

made

by

Microswitch. In contrast, see

ADL

keyboard.

MIG

An

acronym for Master Image Generator: a high-resolution laser-scanning

printer, based on a photographic process. The

MIG-l

can run up to

2000

bpi, while the slightly different MIG-3 runs at about

800

bpi.

Mockingbird A music system that runs on a Dorado with an attached audio synthesizer

and its keyboard. The goal

of

Mockingbird

is

to relieve the serious composer

of

some

of

the clerical burden

of

writing out scores for music

as

it being

composed.

MType Another early product

of

the system modelling effort: for infonnation, see

[Ivy]<CedarLib)MType)MType.Press

or

ditto. bravo.

name lookup In the context

of

network communications, the process

of

mapping a string

of

characters to a network address.

Also,

the protocol that defines the

mechanism for perfonning such a mapping.

name lookup server A computer that implements the name lookup protocol.

Neptune

An

Alto subsystem providing more sophisticated manipulation

of

the file

system than

is

available with the Executive. See also DDS, which provides

still more bells and whistles at the expense

of

time and space.

NetExec.boot A mini-Executive usable without a disk and obtainable directly from the

Ethernet (from a boot server). The NetExec makes available a number

of

useful stand-alone programs, including CopyDisk, Scavenger, FTP, a number

of

diagnostics, and lots

of

neat games.

network address A pair

of

numbers <network number, host number> that uniquely identifies

any computer in an Internet.

Nursery A large room in CSL, across from the Commons; so named because it

was

to

be where new printers would be nursed to life, and also where fresh blood

(summer interns and the like) would be housed. Does this mean that

Bob

Taylor

thinks

of

graduate students

as

infants? I don't think

so;

course, I could be

wrong...

The

funny windows were intended· to make

it

convenient to hold demonstrations

in the Nursery with some

of

the audience on the outside, looking

in.

OIS

An

acronym for Office Information

~ystems:

a name for a concept, a type

of

product, and (perhaps) a market, not a particular organization.

The Alto-Dolphin-Dorado Briefing Blurb

36

OPD

Orbit

OS

Othello

page (on a disk)

PARC

PARC-place

partition

PasMesa

path name

Penguin

Phylum

physical volume

PIE

An acronym for Office

froducts

Division,

of

which

SnD

is

a part.

A high perfonnance image generator designed to merge source rasters into a

raster

output

stream for a

SLOT

printer (e.g., Dover). So named because

it

ORs bits into buffers.

Acronym for Qperating

~ystem.

Generally used to refer to the Alto

Operating System, which

is

stored in the file Sys.boot. Rarely used locally to

refer to the operating system

of

the same name that runs

on

IBM 360/370

computers.

A network-bootable Pilot utility, good for initializing logical volumes

and

the

like.

A

unit

of

length: an Alto page

is

512 bytes, while an IFS page is 2048 bytes.

Acronym for

~alo

Alto Research

~enter.

Another name for Building

32,

located on Hanover.

A chunk

of

a large local disk that

is

being used to emulate the largest system

disk that the Alto

OS

allows. A Dorado has five partitions, while a Dolphin

has two. Partitions are numbered starting at

1;

the phrase "partition 0"

refers to the current default partition. The current partition

is

use is

determined by the contents

of

some registers that belong to the disk

microcode. You can change these registers with the "partition.""" command

available in the Executive and

in

the NetExec. A (14-sector) partition has

22,736 Alto pages

(11.6

MBtyes). It took a little adroit shoehorning to

fit

two full

partitions onto a Dolphin's

disk:

it turns out that a Shugart

4000

has just one too

few

cylinders to squeeze in

two

full

partitions. So

we

have to

ask

the heads to seek off the end

of

the advertised disk (on the inside, it happens), and put one more cylinder in there!

Ah,

the joys

of

hardware hacking

...

A program that more

or

less compiles Pascal source into Mesa source,

and

hence assists in importing Pascal programs into

our

environment; developed

in CSL.

A complete description

of

a directory

or

subdirectory on which files may

be

stored-everything

you need to know to get the file except the file name. A

path name consists

of

a machine name

in

square brackets followed by a

directory name in angle brackets, optionally followed by one

or

more

subdirectory names, each followed by a right angle bracket.

Generic name for a type

of

384 bpi laser-scan printer built

on

the Xerox

5400 xerographic engine,

and

connected to

an

Alto by means

of

an

Orbit

interface. Penguins have better solid-area development than Dovers,

and

can

also print two-sided. They are normally driven with Spruce.

An

IFS

in P ARC-place.

The

name for a disk pack in Pilot.

Acronym for

~ersonal

Information gnvironment. Implemented in Smalltalk,

PIE uses a description language to support the interactive development

of

programs, and to support the office-related tasks

of

document preparation,

electronic mail,

and

database management. For more information, browse

[Ivy]<PIE>.

The Alto-Dolphin-Dorado Briefing Blurb

37

Pilot

Pine

plaid screen

Plate Maker

Poplar

Poseidon

PreCascade

Press

PressEdit.run

PrincOps

printer server

products

An operating system that runs on D-machines, and

was

produced in

SnD

for

us~

by

Star

and future products. Pilot

is

also the current base for Cedar.

The page-level file access protocol used by Juniper.

Occurs when certain kinds

of

memory smashes overwrite the display bitmap

area or control blocks. The term "salt & pepper" refers to a different pattern

of

similar origin.

An old name for the MIG.

An

interactive programming language system running

on

the Alto, an

experimental system in the direction

of

programming

by

relatively

inexperienced users. Useful for text manipulation applications.

A Tool that provides the functionality

of

Neptune in the PreCascade

environment.

The current version

of

an interim integrated Mesa development facility based

on Pilot. A future version (and a prior version, confusingly enough)

will

be

(was)

called simply Cascade. When operating in PreCascade, editing, compiling,

binding, and creature comforts all happen inside

of

the CoPilot world. A

world-swap occurs to the Pilot world only when actually trying out the

program currently undergoing development

A

file

format used to encode documents

to

be transmitted to a printer. Also,

a printing server program, written in BCPL, that can print curves

and

raster

images

as

well

as

characters and rules.

A subsystem that recombines Press files on a page-by-page basis;

it

can also

merge illustrations into documents, although requesting this

is

a somewhat

arcane and delicate operation.

The Xerox Mesa Processor Principles

of

QQeration, essentially a description

of

a particular abstract machine. D-machines implement the PrincOps

architecture, and Pilot

was

constructed to run on PrincOps machines.

A computer that provides printing services, usually for files formatted in a

particular

way.

The term also refers to the specific software that converts

such files into a representation that can be processed by a specific printer

hardware interface. Spruce

is

an example

of

a printer server program.

The following is a list

of

the most commonly encountered Xerox product

numbers and their distinguishing characteristics:

800

860

2600

3100

4500

5400

5700

6500

7000

8000's

typewriter-based, word-processing terminal

display-based, word-processing terminal

desktop copier

3 sec/page copier, good solid black-area development

1 sec/page copier, 2-sided copying

1 sec/page copier, good resolution

1 sec/page laser-scan printer

20

sec/page copier, color copying

1 sec/page copier

the parts

of

Star

have numbers in this range

The Alto-Dolphin-Dorado Briefing Blurb

38

PSD

Puffin

PUP

Quake

R-Name

registry

Rem.cm

replay

Reticle Generator

Rockhopper

Rubicon

rule

Scavenger.boot

Science Center

scroll

SDD

SettingUpPilot

SIL.run

server

9200

o ffset-qu ali

tYt

.5

sec/page copier

9700

offset-qualitYt

.5

sec/page, laser-scan printer

Acronym

for

~rinting

~ystems

Division.

Generic name for a type

of

384

bpi laser-scan color printer built on the

Xerox

6500

xerographic enginet and normally driven by Press.

Acronym for PARC Universal Packet. The structure used to transmit blocks

of

information (packets) on the -Ethernet.

Also,

one such unit

of

information:

a datagram.

Bob

Metcalfe once remarked that this name

was

chosen since all prior P ARC

communication protocols were "real dogs" .

A Dover on the first floor

of

Building

35.

A complete name from Grapevinets point

of

view:

R-names have

two

parts, a

prefix and a registry separated

by

a dot,

as

in

"Anderson.P

AH.

R-names that

designate distribution lists end in an

"t",

as

in "CSLt.PA".

A concept used by Grapevine to partition the space

of

names. "PA",

"WBST"t and "EOS" are examples

of

registries.

A

file

used by the Alto Executive

to

store commands to be interpreted after

the current one has completed. See Com.cm.

Refers

to

a Bravo facility that permits recovery after a crash. See BravoBug.

A version

of

the MIG that

will

print directly on masks for integrated circuits.

A Penguin in the Bayhill building.

The current release

of

Pilot.

A printing term describing a rectangle whose sides are parallel to the

coordinate axes; usually thin enough in one dimension or the other to be

thought

of

as

a (horizontal

or

vertical) line.

A program available through the NetExec that checks for damaged file

structures in a BFS and tries to repair them.

Half

of

PARC; the other half

is

the Systems Center. The rationale behind

the specifics

of

the division are unclear.

Refers

to

a method

of

repositioning text on a display

as

though it were part

of

a long, continuous sheet

of

paper.

Acronym

for

~ystem

Development Division, a part

of

OPD.

A memo on how to set up a Pilot world on a Dolphin and Dorado, with lots

of

good dope on what is really going on; available on [Ivy]<Pilot}Doc}.

Acronym for Simple ILlustrator. An illustrator program used for logic design

and drawing

In

general. A weird but efficient user interface; solid performance.

A computer dedicated to performing some collection

of

service functions for

the communal good

{e.g'

t a printer

server}.

The Alto-Dolphin-Dorado Briefing Blurb

39

SLOT

Smalltalk

Snapshot

Acronym for

~canning

!:aser Output Transducer.

An

integrated programming system based on object style and message

passing, invented and developed by LRG.

Another early product

of

the system modelling effort, now mostly used

to

clean up partitions

by

means

of

the "deleteall" option. For more data, see

[I

vy]<CedarLib)Snapshot>Shapshot.press or ditto.bravo.

solid-area development The ability

of

a printer to produce large areas

of

black. Requests for large

black areas on printers like Dovers, which don't have this ability, will result

in a fringe

of

dark gray around a sea

of

light gray.

Spruce

SSL

Star

Stinger

subdirectory

subsystem

Swat

Swatee

Sys.boot

SysDir.

SysFont.al

A program that takes certain simple Press

files

(primarily text and rules),

converts them

to

a form acceptable by an Orbit interface, and prints them.

Acronym for §ystem

~cience

1aboratory, a former part

of

the Science Center

of

PARC.What

used to be SSL

now

exists

as

a collection

of

"groups" or

" areas" (of

which

the author

does

not have a

very

good

model).

An OIS product

of

Xerox, developed within SDD.

Also

referred to by

various product numbers in the 8000's. The primary professional workstation

of

Star

is

the

8010.

The

8000

architecture

was

created in CSL.

A Hornet located in ISL, running Press.

File directories on an IFS can be divided into a hierarchical collection

of

subdirectories. The subdirectory names are listed from the top

of

the tree

down

to

the bottom, and are separated

by

the single character

")".

For

example, the directory [lvy]<CedarLib) has a subdirectory called MakeConfig

on which

files

related to the MakeConfig program or stored. To refer to the

file

MakeConfig.Press on this subdirectory, one would write:

[Ivy]<CedarLib)MakeConfig)MakeConfig.Press

A program running under a specific operating system. Normally used to

refer to Alto programs that run under the Alto OS, but also used to refer to

PDP-IO programs that run under TENEX.

A debugger used primarily for BCPL programs.

Also,

the

key

used in

conjunction with the "control" and "shift" keys to invoke the debugger.

Used

as

a verb

to

refer to the act

of

striking these keys or entering the

debugger.

A

file

used

by

debugging programs (both Swat and the Mesa debugger) to

hold the core image

of

the program being debugged. Also used

as

a scratch

file

by many Alto subsystems. Not

to

be deleted under any circumstances.

An Alto disk

file

containing the executable representation

of

the Alto

Operating System.

The Alto. file directory. Roughly speaking, this file contains the mapping

from

file

names

to

starting disk locations.

An Alto screen font used by the Executive and (generally)

as

a default by

other programs. The safestway to change your SysFont

is

with

the Delete.- and Copy.-

commands of the Alto

Executive.

Simply FfP'ing a

new

font

on

top

of

SysFont

will

cause

exotic behavior during the CounterJunta

when

FfP

is

finished.

The Alto-Dolphin-Dorado Briefing Blurb

40

system modelling A part

of

the Cedar project, aiming at giving programmers help

is

describing

th~

structure

of

large systems: getting all the versions correct and the like.

Systems Center Half

of

PARC; the other half

is

the Science Center. The rationale behind

the specifics

of

the division are unclear.

Tajo

An

environment

for

developing Mesa programs that exists in both Alto and

Pilot versions; this environment comes complete with a consistent

philosophy about many things, including how screen space should be used,

which window should be listening

to

the keyboard at any given moment, and

much more. Each facility in the Tajo environment

is

called a Tool, and Tajo

itself

was

once called the Tools Environment.

Telnet A PUP-based protocol used to establish full-duplex, teletype-like

communication with a remote computer. (The term

is

borrowed from a

similar protocol used on the Arpa network.) Chat speaks this protocol.

Tenex An operating system for the DEC

PDP-IO

computer, which also runs on

MAXC.

TEX A document compiler written by Don Knuth at Stanford; there are two

implementations

of

TEX at PARC, one

in

Sail that runs on Maxe, the other

in Mesa for D-maehines. TEX can handle mathematical formulas,

but

doesn't let you

see

anything like what you get.

thumbing A technique

of

positioning a file (usually text)

to

an arbitrary position,

usually for viewing on a display.

Tioga A project in ISL to build an integrated editor/typesetter

in

Mesa.

Tool A facility available in the Tajo environment,

or

the program that makes that

facility available. For example, one speaks

of

the "File Tool", which can

perform

file

transfers for you.

Tools Environment Former name for Tajo.

transaction A collection

of

reads and writes

of

shared data that

is

guaranteed to be

atomic: either all

of

the writes happen (the transaction commits)

or

none

of

them do (it aborts). Furthermore, the reads

will

see consistent data in that

either all

of

the writes made by some other transaction

will

be

visible,

or

none

of

them

will.

typescript

An

Alto file used to back-up information (usually text) appearing in a region

of

the display.

Twinkle A Gateway in Building 35

of

PARCo

Universal File System At the moment, merely a dream: in particular, the dream that someday all

of

our files

will

live in a common system, implemented in a distributed

and

reliable fashion

by

remote servers, for which all local disks will merely be

automatically-managed caches. There

is

some hope that this dream

will

be

turned into reality someday

by

something to be built on top

of

Cedar

and

Alpine.

user A person (rather than a program) who avails herself

of

the services

of

some

program or system. At the moment, the author

is

a user

of

Bravo. See

client.

The Alto-Dolphin-Dorado Briefing Blurb

41

user.cm

WaterLily

window

Wonder

world-swap

XBS

XEOS

XGP

XM

Yoda

Zinfandel

A

file

containing a number

of

logically distinct sections that each define

certain configuration parameters (e.g., the location

of

a preferred printer

server for a particular

file

format). Programs that interpret such parameters

are often organized to read user.cm

only

at installation time (e.g., Bravo).

A Mesa program that does source compares: compares two text files and

reports the differences. A vailable in both Alto/Mesa and PreCascade.

A display region,usually rectangular, used to

view

(a

portion of) an image

that generally exceeds the bounds

of

the region.

A Dover on the third floor

of

Building

35.

The process

of

writing out the complete state

of

a machine's processer and

memory onto a disk

file,

and

of

swapping in a different state. Most

of

the

debuggers in our current environment work

by

means

of

world-swaps, which

swap between the debugger and the program being debugged. Note that, the

more memory

you

have. the slower a world-swap

will

be.

Acronym for Xerox Business

~ystems;

a former organization,

XBS

was

subsumed by

OPD.

-

An IFS located at EOS.

Acronym for Xerox Graphics Printer.

An

obsolete, CRT scanned,

200

bpi,

continuous paper, xerographic printer.

Acronym for E!tended Memory: an option on Alto II's that allows the

memory size to be increased from one to four banks. .

A Dover located at PARe-Place.

An Alto mail server that

is

part

of

the Grapevine distributed transport

mechanism.

The Alto-Dolphin-Dorado Briefing Blurb

42

References

Reference numbers

in

[square brackets] are

for

conventional, hardcopy documents. Reference

numbers

in

{curly brackets} are

for

on-line docUlnent

files.

The notation used

for

on-line

files

is:

[FileServer]<Directory)SubDirectory)FileName.Extension .

Each reference

is

followed

by

a brief description

of

what

you

can expect

to

find

in

the cited

document.

If

you

can't find some

of

the on-line

files,

they

may

have been archived. See the section on

"Looking Under Rocks" .

{I}

[M

axc]

< AltoDocs) AltoHardware.press

[2]

Metcalfe,

R.

M.

and

Boggs,

D.

R.

Ethernet: Distributed Packet Switching

for

Local

Computer Networks. Communications

of

the

ACM

19,

7 (July

1976),

pp.

395-404.

A

description

of

the Ethernet's functional organization, with a discussion

of

error recovery

strategies.

{3}

[Maxc]<AltoDocs)NetTopology.press. Contains a picture

of

the entire internetwork

configuration: currently four pages.

{4}

[Maxc]<Pup)FTPspec.press. A functional specification

of

the

file

transfer protocol,

independent

of

implementation in any particular language or system.

{5}

[Maxc]<Pup)EFTPspec.press. A functional specification

of

the "easy"

file

transfer protocol.

{6}

[Maxc]<Pup)Telnet.press. A functional specification

of

a protocol

for

interactive teletype-

like communication between computers on the network.

{7}

[Maxc]<Pup)MiscServices.press. Describes a variety

of

simple protocols (usually a single

exchange

of

packets).

{8}

[Maxc]<AltoDocs)OS.press. The programmer's reference manual

for

the Alto Operating

System, including detailed information on the services provided and the interface

requirements.

[9]

Myer,

T.

H. and Barnaby,

1.

R.

TENEX Executive Language Manual

for

Users. Available

from Arpa Network Information Center

as

NIC

16874,

but in the relatively unlikely event

that

you

need one, borrow one from a Tenex

wizard.

{10}

[Maxc]<AltoDocs)SubSystems.press. Documentation on individual Alto subsystems,

collected in a single

file.

Individual systems are documented

on

[Maxc]<AltoDocs)systemname.TIY, and these

files

are sometimes more recent than

SubSystems. press.

[11]

Morris,

1.

H. The Elements of Mesa Style. Xerox PARC Internal Report, June

1976.

Somewhat out

of

date (since Mesa has changed under it), but a readable introduction to

some useful program structuring techniques in

Mesa.

[12]

Jerome, Suzan.

Bravo

Course Outline. Xerox PARC Internal Report, undated. Oriented

to non-programmers.

[13]

Alto User's Handbook. Xerox PARC Report, November

1978.

An introduction to Alto

facilities and reference documentation for several commonly used subsystems, including

Bravo, Laurel, FfP, Draw, Markup, and Neptune.

The Alto-Dolphin-Dorado Briefing Blurb

43

[14]

Sunset Western Garden Book. Lane Magazine and

Book

Company, Menlo Park, Ca. The

definitive

docun~ent

on Western gardening for non-botanists.

{IS} [Maxc]<Pup)Gateway Infonnation.press. Describes the protocol for obtaining packet routing

information from the Gateways.

{16}

[Maxc]<Pup)Pup.press. A functional specification

of

the PUP mechanism for packet-based

communication on the network.

{17}

[I

vy

]<Laurel)Laure1.press. Documentation for the Alto-based, electronic mail system. Also

available

as

blue-and-white report CSL-81-6

..

{18}

On-line documentation for Smalltalk

is

(always?) in a state

of

flux.

Consult a member

of

LRG for a current pointer.

[19]

Maybury,

W.,

Mitchell,

1.

G., and Sweet,

R.

Mesa

Language Manual. Xerox

PARe

Internal Report CSL-79-3, April,

1979.

A cross between a tutorial and a reference manual,

though much closer

to

the latter than the fonner. Details

of

the Alto implementation

appear in other, on-line documentation-look on

[Ivy]<Mesa>.

{20} [Maxc]<AltoDocs)AltoUsersPrimer.press. A more complete (and neutral) introduction to

Alto-land, intended at least in part for non-programmers.

{21}

[Maxc]<PrintingDocs)Printing.press. The "entry document" for printing services on Maxc

and the Alto.

[22]

Kay,

A.

C.

"Microelectronics and the Personal Computer". Scientific American,

September,

1977,

pp.

230-244.

[23]

Personal Dynamic Media. Xerox LRG/SSL report 76-1,

1976.

{24} [Ivy]<DoradoDocs)DoradoBooting.press. The operation and mechanisms

of

booting a

Dorado.