atc - air traffic controller game
atc [-lpqstu?] [-fg game name] [-r random seed]
atc lets you try your hand at the nerve-wracking duties of
an air traffic
controller without endangering the lives of millions of
year. Your responsibilities require you to direct the
flight of jets and
prop planes into and out of the flight arena and airports.
(update time) and frequency of the planes depend on the difficulty of the
-f game Play the named game. If the game listed is not
one of the ones
printed by the -l option, the default game is
-g game Same as -f.
-l Print a list of available games and exit. The
first game name
printed is the default game.
-p Print the path to the special directory where atc
find its private files. This is used during the
of the program.
-q Play quietly (no bells).
-s Print the score list (formerly the Top Ten list).
information is the game time in ``radar updates'',
game time, and the number of planes that
-t Same as -s.
-r seed Set the random seed. This option can be used to
replay a specific
-u Print the usage line and exit.
-? Same as -u.
Your goal in atc is to keep the game going as long as possible. There is
no winning state, except to beat the times of other players.
need to: launch planes at airports (by instructing them to
altitude); land planes at airports (by instructing them to
go to altitude
zero when exactly over the airport); and maneuver planes out
Several things will cause the end of the game. Each plane
has a destination
(see information area), and sending a plane to the
is an error. Planes can run out of fuel, or can collide.
defined as adjacency, horizontal or vertical. A plane leaving the arena
in any other way than through its correct destination exit
is an error as
Scores are sorted in order of the number of planes safe.
statistics are provided merely for fun. There is no penalty
longer than another player (except in the case of ties).
Suspending a game is not permitted. If you get a talk message, tough.
When was the last time an Air Traffic Controller got called
away to the
Depending on the terminal used, the atc screen will be divided into 4 areas.
It should be stressed that the terminal driver portion
of the game
was designed to be reconfigurable, so the display format can
on the version you are playing. The descriptions here
are based on
the ASCII version of the game. The game rules and input
should remain consistent. Control-L redraws the screen,
should it become
RADAR [Toc] [Back]
The first screen area is the radar display, showing the relative locations
of the planes, airports, standard entry/exit points,
and ``lines'' which simply serve to aid you in guiding the
Planes are shown as a single letter with an altitude. If
altitude is a single digit, then it represents thousands of
distinction is made between the prop planes and the jets.
On ASCII terminals,
prop planes are represented by an upper case letter,
jets by a
lower case letter.
Airports are shown as a number and some indication of the
planes must be going to land at the airport. On ASCII terminals, this is
one of `^', `>', `<', or `v', to indicate north (0 degrees),
west (270), and south (180), respectively. The planes will
also take off
in this direction.
Beacons are represented as circles or asterisks and a number. Their purpose
is to offer a place of easy reference to the plane pilots. See The
Delay Command under the input section of this manual.
Entry/exit points are displayed as numbers along the border
of the radar
screen. Planes will enter the arena from these points without warning.
These points have a direction associated with them, and
planes will always
enter the arena from this direction. On the ASCII version of atc,
this direction is not displayed. It will become apparent
what this direction
is as the game progresses.
Incoming planes will always enter at the same altitude: 7000
feet. For a
plane to depart successfully through an entry/exit point, it
must be flying
at 9000 feet. It is not necessary for the planes to be
flying in any
particular direction when they leave the arena (yet).
INFORMATION AREA [Toc] [Back]
The second area of the display is the information area,
which lists the
time (number of updates since start) and the number of
planes you have
directed safely out of the arena. Below this is a list of
in the air, followed by a blank line, and then a list
of planes on
the ground (at airports). Each line lists the plane name
and its current
altitude, an optional asterisk indicating low fuel, the
and the plane's current command. Changing altitude is
to be a command and is therefore not displayed. The
some possible information lines:
B4*A0: Circle @ b1
g7 E4: 225
The first example shows a prop plane named `B' that is flying at 4000
feet. It is low on fuel (note the `*'). Its destination is
The next command it expects to do is circle when it reaches
The second example shows a jet named `g' at 7000 feet, destined for Exit
#4. It is just now executing a turn to 225 degrees (Southwest).
INPUT AREA [Toc] [Back]
The third area of the display is the input area. It is here
input is reflected. See the INPUT heading of this manual
for more details.
AUTHOR AREA [Toc] [Back]
This area is used simply to give credit where credit is due.
A command completion interface is built into the game. At
any time, typing
`?' will list possible input characters. Typing a
erase character) backs up, erasing the last part of the command. When a
command is complete, a return enters it, and any semantic
done at that time. If no errors are detected, the command
is sent to the
appropriate plane. If an error is discovered during the
check, the offending
statement will be underscored and a (somewhat) descriptive message
will be printed under it.
The command syntax is broken into two parts: Immediate Only
commands. Immediate Only commands happen on the next update. Delayable
commands also happen on the next update unless they are followed by an
optional predicate called the Delay command.
In the following tables, the syntax [0-9] means any single
<dir> refers to the keys around the `s' key, namely ``wedcxzaq''. In absolute
references, `q' refers to Northwest or 315 degrees,
and `w' refers
to North, or 0 degrees. In relative references, `q' refers
to -45 degrees
or 45 degrees left, and `w' refers to 0 degrees, or no
All commands start with a plane letter. This indicates the
the command. Case is ignored.
IMMEDIATE ONLY COMMANDS [Toc] [Back]
a [ cd+- ] number
Altitude: Affect a plane's altitude, possibly requesting takeoff.
`+' and `-' are the same as `c' and `d'.
a [0-9] Go to the given altitude (thousands of
c [0-9] Climb: Relative altitude change (thousands
d [0-9] Descend: Relative altitude change (thousands of feet).
m Mark: Display in highlighted mode. Plane and command
is displayed normally.
i Ignore: Do not display highlighted. Command information is displayed
as a line of dashes if there is no command.
u Unmark: Same as ignore, but if a delayed command is
plane will become marked. This is useful if you want
about a plane during part, but not all, of its journey.
DELAYABLE COMMANDS [Toc] [Back]
c Circle: Have the plane circle.
t [ l-r+LR ] [ dir ] or tt [ abe* ] number
Turn: Change direction.
t<dir> Turn to the absolute compass heading given. The shortest
turn will be taken.
tl Left: Turn counterclockwise (45 degrees by
tl <dir> Turn ccw the given number of degrees. Zero
degrees (`w') is no turn; 45 degrees ccw is
`e'. The shortest turn will be
instance, if you specify a ccw
turn of 315
degrees (`q'), which should take
turns, the plane will really
turn 45 cw,
which takes only one turn.
tr Right: Turn clockwise (45 degrees by default).
tr <dir> Analogous to turn left <dir>.
tL Turn counterclockwise 90 degrees.
tR Turn clockwise 90 degrees.
tt [abe*] Towards: Turn towards a beacon, airport or
turn is just an estimate.
ttb number Turn towards the specified
tt* number Equivalent to ttb.
tte number Turn towards the specified exit.
tta number Turn towards the specified
THE DELAY COMMAND [Toc] [Back]
The Delay (a/@) command may be appended to any Delayable
command. It allows
the controller to instruct a plane to do an action when
reaches a particular beacon (or other objects in future versions).
a/@ At: Do the given delayable command when the
the given beacon.
ab number The letter is redundant to allow
`@' can be used instead of `a'.
MARKING, UNMARKING AND IGNORING
Planes are marked by default when they enter the arena.
This means they
are displayed in highlighted mode on the radar display. A
plane may also
be either unmarked or ignored. An unmarked plane is drawn
mode, and a line of dashes is displayed in the command field of
the information area. The plane will remain this way until
a mark command
has been issued. Any other command will be issued, but
line will return to a line of dashes when the command is
An ignored plane is treated the same as an unmarked plane,
except that it
will automatically switch to marked status when a delayed
been processed. This is useful if you want to forget about
a plane for a
while, but its flight path has not yet been completely set.
As with all of the commands, marking, unmarking and ignoring
effect at the beginning of the next update. Do not be surprised if the
plane does not immediately switch to unhighlighted mode.
EXAMPLES [Toc] [Back]
atlab1 Plane A: turn left at beacon #1
cc Plane C: circle
gtte4ab2 Plane G: turn towards exit #4 at beacon #2
ma+2 Plane M: altitude: climb 2000 feet
stq Plane S: turn to 315
xi Plane X: ignore
+o Jets move every update; prop planes move every other update.
+o All planes turn at most 90 degrees per movement.
+o Planes enter at 7000 feet and leave at 9000 feet.
+o Planes flying at an altitude of 0 crash if they are not
over an airport.
+o Planes waiting at airports can only be told to take off
+o Pressing return (that is, entering an empty command)
will perform the
next update immediately. This allows the player to
the game clock if nothing interesting is happening.
The Game_List file lists the currently available play
fields. New field
description file names must be placed in this file to be
playable. If a
player specifies a game not in this file, his score will not
The game field description files are broken into two parts.
part is the definition section. Here, the four tunable game
must be set. These variables are set with the syntax:
variable = number;
Variable may be one of: update, indicating the number of
forced updates; newplane, indicating (about) the number of
new plane entries; width, indicating the width of the
or height, indicating the height of the play field.
The second part of the field description files describes the
the exits, the beacons, the airports and the lines. The
syntax is as
beacon: (x y) ... ;
airport: (x y direction) ... ;
exit: (x y direction) ... ;
line: [ (x1 y1) (x2 y2) ] ... ;
For beacons, a simple x, y coordinate pair is used (enclosed
parentheses). Airports and exits require a third value, a
which is one of ``wedcxzaq''. For airports, this is the direction that
planes must be going to take off and land, and for exits,
this is the direction
that planes will be going when they enter the arena.
not seem intuitive, but as there is no restriction on direction of exit,
this is appropriate. Lines are slightly different, since
they need two
coordinate pairs to specify the line endpoints. These endpoints must be
enclosed in square brackets.
All statements are semi-colon (;) terminated. Multiple item
accumulate. Each definition must occur exactly once, before
statements. Comments begin with a hash (#) symbol and terminate with a
newline. The coordinates are between zero and width-1 and
All of the exit coordinates must lie on the borders, and all of
the beacons and airports must lie inside of the borders.
may be anywhere within the field, so long as the lines are
vertical or exactly diagonal.
FIELD FILE EXAMPLE [Toc] [Back]
# This is the default game.
update = 5;
newplane = 5;
width = 30;
height = 21;
exit: ( 12 0 x ) ( 29 0 z ) ( 29 7 a ) (
29 17 a )
( 9 20 e ) ( 0 13 d ) ( 0 7 d ) (
0 0 c ) ;
beacon: ( 12 7 ) ( 12 17 ) ;
airport: ( 20 15 w ) ( 20 18 d ) ;
line: [ ( 1 1 ) ( 6 6 ) ]
[ ( 12 1 ) ( 12 6 ) ]
[ ( 13 7 ) ( 28 7 ) ]
[ ( 28 1 ) ( 13 16 ) ]
[ ( 1 13 ) ( 11 13 ) ]
[ ( 12 8 ) ( 12 16 ) ]
[ ( 11 18 ) ( 10 19 ) ]
[ ( 13 17 ) ( 28 17 ) ]
[ ( 1 7 ) ( 11 7 ) ] ;
Files are kept in a special directory, which can be shown by
using the -p
/var/games/atc_score Score file.
/usr/share/games/atc/Game_List The list of playable games.
Ed James, UC Berkeley: email@example.com, ucbvax!edjames
This game is based on someone's description of the overall
flavor of a
game written for some unknown PC many years ago, maybe.
The screen sometimes refreshes after you have quit.
OpenBSD 3.6 May 31, 1993
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