2.2 Using the workstation
The way that a workstation behaves is a function of the type of workstation, the computer operating system, the
window manager program, and the set-up files for the specific computer account being used. Given all these
variables, it is hard to give detailed usage instructions. Nonetheless, it is important for beginning users to master
the foibles of the workstation(s) they will be using.
2.2.1 Logging in to the workstation
Find your assigned computer in the appropriate 
caige or office, or an available one intended for general use
(checking any sign-up sheets for it). Typing C R on the keyboard will reveal the current state of the workstation. If
you see a message prompting you to log in (e.g., AOC RedHat Linux, [monkey] login on a Socorro Linux
workstation named monkey), then the computer is ready for you to log on. Type the account name you are
supposed to use for followed by a C R (use Tab in forms) and then type the password (it will
not be visible on the screen) followed by another C R. See your Manager for the account to
use and its password (which should change with time). Many sites will assign an account to you
personally, while some use a more generic AIPS account. The login scripts should start the window
system automatically and produce one or more xterm or aixterm windows that you can use for starting
AIPS.
If the initial C R produces instead a set of windows (and/or icons), the computer is already being used. If
these windows include the AIPS TV and possibly the TEKSRV and MSGSRV server windows, it is being
used for AIPS. Check with other possible users before proceeding. If it’s okay to use the system, you
should log the previous user out and log in for yourself, restarting the window system. If you are
patient, you can open each iconified window (by clicking on it once or twice), see what it’s doing and
finish up and/or exit. If the prompt is > in any text window, AIPS is running there and you should
type:
> KLEENEX C R
which will get out of AIPS and kill the servers. Then once at the system prompt (Unix), you can type exit C R
(lowercase!) to make the window go away. If the XAS TV server is still running, just press the escape key
while the cursor is in the TV window. For the MSGSRV message server, move the cursor into the window and press
CTRL C. Finally for the Tek server, hold the control key down while you press the left mouse button, and choose the
QUIT option.
The procedure for exiting from the windowing system will depend on what window manager you use. If your
system uses KDE, there will be an icon on the icon bar with a large K superimposed on a globe. If the system uses
Gnome, then the magic icon is an image of a foot. Move the mouse to the icon and hold down the left button. A
pull-down menu will appear; select the Logout function.
2.2.2 Control characters on the workstation
To correct characters which you have typed, you may have to press either the BackSpace key or the Delete (or DEL)
key. Unfortunately, which is required varies with the application you are using and how the AIPS account (or your
personal account) has been set up. For details, see the manual page on stty with particular note of the erase
function.
A control character is produced by holding down the CTRL (or Control) key while hitting another key. Some control
characters under Unix have characteristics that may confuse users more used to other environments (VMS,
MS-DOS). In particular, CTRL D, CTRL T, CTRL Y and CTRL Z behave much differently under Unix than under VMS.
CTRL D is used in Unix as a signal to logout, unless otherwise inhibited. If you use the AIPS accounts at
either Charlottesville or the AOC, this feature is automatically disabled. While in AIPS, CTRL Ds are
interpreted from the > prompt as an EXIT command. CTRL T (under GNU readline) transposes two
characters, while CTRL Y inserts characters previously saved in the “kill” buffer. CTRL Z suspends the
current process, printing Stopped on your window and leaving you at the Unix prompt level. The
Stopped message does not mean that the process has been terminated. It simply means the process has
been suspended and placed in the background. For users, the suspended process is normally
AIPSn. Users who do not understand this state often start up another session. In doing so,
they are tying up a second number. If a user does this enough times, s/he can eventually tie
up all available AIPSn’s. If you are unfamiliar with the use of CTRL Z (suspend) in Unix systems, it’s
best not to use them from , unless expert advice is close at hand. With an X-Window display, it
is preferable to pop up a new xterm or other window and do whatever you want in it, leaving the
session undisturbed. (You can get a new xterm, usually, by moving the cursor into the root
(background) window, pressing the right mouse button, and selecting the appropriate option.) If you have
suspended the current process (usually AIPS) with CTRL Z to get to monitor level (for instance, to edit
a RUN file), then you can bring the suspended process back into the foreground with the command
fg C R.
To abort any execution in your window, type CTRL C. Using CTRL C while in AIPS will unceremoniously eject you to
the Unix prompt. You will have to restart AIPS with all the input parameters having been lost. In some cases, any
tasks running in the background, and maybe even the TV and other servers, will also be “killed” and will
disappear from the screen. Aborting “tasks” (sub-processes) is usually done from within AIPS
with the command ABORT taskname C R (see §3.1.2) rather than with CTRL C’s or Unix-level system
commands. Not only does this avoid killing AIPS, but it even allows for orderly deletion of scratch
files.
During execution, scrolling of output lines out of the window can be halted by typing CTRL S and resumed by
typing CTRL Q. If you are using an xterm (or cmdtool or aixterm) window with a scroll bar, you probably won’t
have to worry too much about doing this; use the scroll bar to review lines which have rolled off the visible part of
the window. You can specify how many lines these terminal emulator windows remember, e.g., for xterm
with the -ls option or with the X resource xterm*saveLines (in your .Xdefaults or .Xresources
file).
2.2.3 Starting the AIPS program
As you enter the commands needed to log in to your system and start AIPS, please read all messages which appear.
They are often important and relate to current system, disk, and problems which may affect your
reductions.
To begin AIPS, enter
% aips C R | with no options initially |
You will then be shown a list of printer devices and be prompted to Enter your choice:. You will then be told
about the assigned printer queue and data disks. If all is going well it will then tell you
You seem to be at a workstation called monkey
Starting local TV servers on monkey
where monkey is the name of your workstation. Any news messages about your installation will then
appear. Read them; they might be important. Finally, you should see the messages:
Starting up 31DEC24 AIPS with normal priority
BEGIN THE ONE TRUE AIPS NUMBER n (release of 31DEC24) at priority 0
where 31DEC24 identifies the release of and n is a number between 1 and 6 (typically). If this is the only
session on the computer, you should be assigned n = 1, with higher numbers used for additional sessions. If
you start with n > 1, someone else may be using your computer remotely. AIPS will then tell which TV and
graphics devices have been assigned to you:
AIPS n: You are assigned TV device nn
AIPS n: You are assigned graphics device mm
where nn and mm are numbers assigned to your workstation (or, rarely now, to real TV and graphics devices). AIPS
will now ask you for your user number and provide a ? prompt:
AIPS n: Enter user ID number
? uuuu C R
where uuuu is the number assigned to you for the local system (in decimal form). The AIPS prompt > should
now appear.
There is more. Notice the line above that says “starting local TV servers on monkey”? At that
point, the process of figuring out what computer you’re running on and what display you’re sitting at
(they may be different) is shed in an asynchronous way while the main process of starting the AIPS
program proceeds. Then, sometime later, you will see the following messages appear in the same
window:
XASERVERS: Start TV LOCK daemon TVSERV on monkey
TVSERVER: Starting AIPS TV locking, Inet domain
XASERVERS: Start XAS on monkey, DISPLAY monkey:0
XAS: ** TrueColor FOUND!!!
XAS: *** Using shared memory option for speed ***
XAS: Using screen width height 2540 1920
max grey level 8191 in 16 grey-scale memories
characters multiplied by 2
XASERVERS: Start graphics server TEKSRV on monkey, DISPLAY monkey:0
XASERVERS: Start message server MSGSRV on monkey, DISPLAY monkey:0
Each of the first four messages should announce the starting of one of the servers. The Tek server will appear in
iconified form somewhere on the screen, while the message server will appear opened (not iconified) somewhere
else. Finally, the XAS TV server appears in opened form. An environment variable can be set to have the Tek server
appear in open form and a .Xdefaults (or .Xresources) file option may be set to have the TV appear in
iconified form. If your X-Windows supports 24-bit TrueColor, then XAS will use it. Otherwise, XAS
will use 8-bit PseudoColor which is faster but less flexible. In this case, if you have a lot of colors
in your X11 display (e.g., an image on the root window displayed with xv), you may also get the
message:
XAS: Using screen width height 1142 800, max grey level 189
XAS: Warning -- creating virtual colormap
which means XAS wasn’t able to find enough free colors in the main colormap (189 in the above example) and had
to create its own. In this case, the colors of every other window will “flash” when you move the mouse cursor into
the opened XAS TV window, and vice versa. You can use xsetroot -solid navy command (or other legal X colors)
to blank out whatever is on the root window; then restarting AIPS will restart the TV server, hopefully without
a virtual colormap. There are a number of X-Window parameters which may be specified in your
.Xdefaults or .Xresources file for these three windows. After AIPS begins, type HELP XAS C R, HELP
MSGSRV C R, and HELP TEKSRV C R for details. Among these is a parameter controlling how many
colors XAS tries to use in PseudoColor and whether it tries to use TrueColor or not. Character size
multiplication occurs by default when you have a large number of pixels on your screen. It can be controlled
by an .Xresources parameter and the AIPS verb CHARMULT. See §2.3.2 for more information about
XAS.
There are several options you can use in starting up AIPS. To see them, just enter man aips at the Unix command
prompt, or if you are already in AIPS, type HELP AIPS C R. This information is reproduced in part
below:
aips [OLD, NEW, or TST]
[TV=[disp][:][host]]
or [TV=local[:n]]
or [TV=inet]
or [NOTV]
[TVOK]
[DA=host[,host,...]]
or [DA=default]
or [DA=all]
[PR=#]
[REMOTE or REM or TEK]
[DEBUG[=prog][:aips]]
[LOCAL] [NORL] [NOEX]
DESCRIPTION
The aips or AIPS command starts up the AIPS command interpreter and
associated AIPS server processes.
OPTIONS
All command line options are case insensitive.
AIPS allows up to three versions to co-exist (disk space permitting) in one
installation. They are identified either by date (e.g. 31DEC24) or name
(OLD, NEW, or TST). On most installations, these will all be the same.
OLD Start the OLD version of AIPS. For NRAO this is a frozen version
which has been distributed worldwide. Serious bugs are rarely
corrected.
NEW Start the NEW version of AIPS. For NRAO this is the most recently
released version and is "frozen" at the date in its name.
Serious bugs are corrected over the next year.
tst Start the TST version of AIPS. For NRAO this is the development
version which is also available to non-NRAO sites. This is the
default.
TV=[tvdisp][:][tvhost] or TV=local[:n] or TV=inet
The default TV display server is now (31DEC24) TV=local:0.
TV display server to use instead of the default. The AIPS startup
script tries to deduce which host the user is sitting in front of
(this may not work; it is often difficult or impossible to determine
this information). This may not be the same as the machine on which
AIPS is to be run if, for example, the user has remotely logged in to
another machine within a terminal emulator window.
The "TV=local" option allows use of Unix based sockets for the TV and
other servers. If you choose this option, you MUST run the XAS server
and any AIPS sessions that will use it on the same host, though the
DISPLAYs can be the same or different. Also, no remote AIPS sessions
will be able to talk to this local TV.
If you instead use "TV=local:0", it will attempt to start a new
instance of the TV and ancillary servers. This can be used to have
multiple TV’s on the same host, and is useful in a compute server
environment with X terminals. If you have multiple Unix-socket based
TV’s already started, you can choose which one a new AIPS session will
use by, e.g. "TV=local:2" to choose the second one. Note that the
n in ‘‘TV=local:n’’ is in extended HEX or 0 to 9, A to Z.
NOTE: The default TV behavior is no longer to use internet
based sockets. Such use is mostly when more than one
computer must talk to the same incarnation of XAS, which is
an uncommon usage. Internet sockets also require compatible
entries in the system file /etc/services.
For the use of internet sockets, the full syntax of the TV= option
is TV=tvdisp:tvhost, where tvhost is the name of the machine on which
the TV display server (usually XAS), Tektronix graphics server
(TEKSRV), message server (MSGSRV), and TV Lock server (TVSERV) are to
run, and tvdisp indicates the machine to which the DISPLAY environment
variable should point for XAS. Do NOT specify TV=hostname:0.0! Both
TVHOST and TVDISP can be different from the machine that AIPS itself
is running on. See the section on X Window System servers below for
more information on how to control the servers.
The default behavior of this option if only one of tvdisp and tvhost
is specified is
TV=tvhost tvdisp defaults to tvhost.
TV=tvdisp: tvhost defaults to the host AIPS is running on.
TV=:tvhost tvdisp defaults to the host AIPS is running on.
For the remote TV options to work, you must be able to use the rsh or
remsh command; see the notes on it under the tp= heading below. Also
see the notes on environment variable AIPSREMOTE. By default, if you
do not specify any tv= option, you will only get a TV if your current
TERM environment variable matches sun*, *xterm*, *hpterm, dtterm, or
iris*. The DISPLAY environment variable is used if set, otherwise the
who am i (on HP-UX, with the -R option) is used to make a guess at
"where" you really are.
NOTV Prevents automatic activation of the TV server if no display is
wanted. This option also disables the Tektronix graphics server, the
message server and the TV lock server. See the section on X Window
System servers below for information on how to control the Tektronix
and message servers.
TVOK Assume that the TV display servers are already running; the particulars
(display, host) are still worked out -- from the TV=... argument
(see above) if necessary -- but no servers will be started.
DA=host[,host,...] or DA=default or DA=all
Select user data areas (directories, or "disks" in AIPSpeak) that are
local to the (comma separated) list of machines. Data areas from
"required" hosts and those on the local machine are always added,
regardless of the list of hosts.
All disks from each named host will be assigned. Use the FREE command
within AIPS to see the disk assignments you end up with. They are
also shown on startup.
AIPS has a limit of 35 disks in any one session. The limit on the
number of disks that can be defined for any given site is 512. Disk 1
is special in that it stores the AIPS message and save/get files. The
system is designed so that one particular required disk will almost
always be assigned as disk 1. For performance reasons, this may be
undesirable if the filesystem in question is mounted via NFS. See the
description of personal .dadevs files below, as it can be used to cus-
tomize the list of possible user data areas.
Selecting DA=ALL will try to include every area defined in the startup
file, up to the session limit. Bear in mind that most AIPS tasks only
have 10 slots for "BADDISK". Selecting DA=DEFAULT will completely
bypass the configurable data areas and choose only those data areas
pre-configured by the AIPS manager; THIS IS NOT NORMALLY ENABLED, CHECK
WITH YOUR AIPS MANAGER BEFORE USING DA=DEFAULT.
There is a hierarchy of data area "lists" that AIPS will look for on
startup. These are:
$HOME/.dadevs This would be in your private login area (what
$HOME points to). It need not exist. If it
doesn’t, AIPS looks for the next file:
$DA00/DADEVS.LIST This is a host-specific file possibly set up by
the AIPS manager. If it doesn’t exist, AIPS
finally looks for:
$NET0/DADEVS.LIST which is the site-wide data area configuration
file.
The normal state of affairs is to have just one place for disks to be
defined, namely $NET0/DADEVS.LIST. Your AIPS manager can choose to
install host-specific list files, and you can choose (if you run AIPS
from your own private account) to override both of these two with your
own private version. This allows for considerable flexibility but
moves the onus of maintenance of these files to the user. In other
words, if you have your own .dadevs file, you have to keep track of
your site’s disk configuration!
If your AIPS installation supports multiple sites, e.g. to support
both little-endian (Intel, Mac) and big-endian (Sparc) systems, you
can have any of these files refer to one or the othe site by appending
the site name, e.g. $HOME/.dadevs.VCOARN for SITE=VCOARN.
The format for these files is all the same: a list of directory names
preceded by a "+" for required or a "-" for optional. There should be
two (2) spaces between the "+" or "-" (in the leftmost column) and the
directory name.
In addition to all of the above, you may define a list of data areas
in an optional $HOME/.dadevs.always file. This is used in addition to
whichever of the DADEVS files have been selected by the rules above.
The data areas that you will be assigned start with any required data
areas in the $HOME/.dadevs.always file followed by any required data
areas in the selected DADEVS file regardless of name. The 3rd group
of data areas are those optional ones in the selected DADEVS file
containing a string matching the user’s host name. Then come the
optional data areas in the $HOME/.dadevs.always file regardless of
name. Finally, the optional data areas in the selected DADEVS file
with strings matching the names of any hosts given in the
DA=host[,host,...] command-line option. The order of data areas
within each group, i.e. which is disk 1, etc., is determined by the
order in the files.
There is also a $NET0/NETSP file that is maintained by the AIPS manager
and controls aips user-number access to the disks. Regardless of
the number of sites in your installation, there is only one NETSP file.
TP=host[,host,...]
Make sure tape servers are running on the comma separated list of
machines. While the AIPS account is usually set up so that it can
perform remote shell (rsh) commands, your personal account may not.
Check with your system administrator or network guru for details.
Also check the Unix manual pages on rsh (remsh on HP-UX), rhosts, and
hosts.equiv. The tp= option uses rsh to issue commands to remote hosts.
TPOK Do NOT check or launch the TPMON tape daemons on the local host. The
default is no longer to check or to start the tape daemons. Therefore,
if you need them, use TP= above even for the current computer.
PR=# Select printer number (e.g., pr=2). If this option is not specified,
the user will be presented with a menu of available printers and
prompted to enter a choice. If there is only one printer configured,
no menu will be presented. You may change the selected printer within
AIPS via the PRINTER adverb.
REMOTE or REM or TEK
Any one of these indicates that the user is running from a terminal
with Tektronix display capability. Graphics output will be sent
directly to this terminal. NOTE: AIPS will not switch from text to
graphics mode on terminals with a separate graphics "screen".
DEBUG[=prog][:aips]
Start AIPS in debug mode. With no arguments, the user will be
prompted for the name of the debugger (e.g. gdb, dbx, adb, csd, xde,
dbxtool, debugger, xxgdb) and also whether to run AIPS itself under
the debugger. If you answer no, only AIPS tasks will be run in debug
mode. If =prog is specified, this suppresses the prompt for the name
of the debugger program. If :aips is specified, this suppresses the
prompt for whether to run AIPS itself in debug mode and assumes it
will. Use of both these options is useful in speeding up the startup
of the system when debugging a program or AIPS itself.
LOCAL Start a local copy of AIPS.EXE residing in the current directory.
Usually used by programmers for debugging purposes.
NORL Disable GNU readline library and command-line editing. This is pri-
marily useful for running backgrounded AIPS sessions, running AIPS
from "here-document" shell-scripts, and for debugging.
NOEX This defers AIPS execution and is not normally used directly by users.
X WINDOW SYSTEM SERVERS
If you are running under the X Window System, AIPS will open up to three win-
dows: a TV window (normally XAS), a message window (MSGSRV) and a graphics
window (TEKSRV). If you specify the notv option on the command line, none of
these will be started.
MSGSRV and TEKSRV are actually simple programs running inside a terminal emu-
lator. You may use any terminal emulator that you would normally use on the
machine on which you are running AIPS for the MSGSRV window. Examples include
xterm (the sample vt100/Tektronix emulator that comes with the MIT X Window
System code); cmdtool and shelltool (the standard terminal emulators for Open-
Windows) and AIXterm (the standard terminal emulator on RS/6000s). You can
choose which one to use by setting the environment variable AIPS_MSG_EMULATOR
to the name of the terminal emulator you wish to use. For example, if you
want to use cmdtool you would type
setenv AIPS_MSG_EMULATOR cmdtool
if you use the C or TC Shell, or
AIPS_MSG_EMULATOR=cmdtool; export AIPS_MSG_EMULATOR
if you use Korn, BASH, or Bourne shells before you start up AIPS. You could
also add these commands to your .login file (C Shell) or .profile
(Korn/BASH/Bourne Shells) to make the assignment more permanent. You can also
give AIPS_MSG_EMULATOR the special value of "none" which will disable the mes-
sage window without affecting the Tektronix window or the TV. If
AIPS_MSG_EMULATOR is not set, the default is xterm.
You may choose the terminal emulator used for the Tektronix window using the
environment variable AIPS_TEK_EMULATOR in the same way that you use
AIPS_MSG_EMULATOR to choose the terminal emulator, but it must support Tek-
tronix graphics codes. On most machines the only values of AIPS_TEK_EMULATOR
that make any sense are xterm and none. If AIPS_TEK_EMULATOR is not set AIPS
will behave as if it were set to xterm. (Note: dxterm, aixterm, and cmdtool
are not "xterm"; they cannot display Tek graphics).
You can set preferences for positions and colors for all three servers using
the standard X Window System mechanisms. Further information is available
through the AIPS HELP system (subjects MSGSRV, TEKSRV, XAS and XVSS).
Note that AIPS expects that a terminal emulator can start a program that is
specified using a -e flag on the command line. This is true of all of the
terminal emulators we know about but if you find one that requires a different
flag you can specify the flag as AIPS_TEK_EXE_FLAG or AIPS_MSG_EXE_FLAG.
ENVIRONMENT VARIABLES
In addition to the Message and Tek server customizations, you may choose to
set a variable AIPSREMOTE to indicate your choice of remote shell command. It
is strongly recommended that the secure shell (ssh) be used in place of the
traditional Berkeley rsh or remsh command:
setenv AIPSREMOTE "ssh -n"
for csh or tcsh shells, or
export AIPSREMOTE="ssh -n"
for bash, korn, zsh and other bourne-like shells.
If you do not specify a printer (by number) on the command line when starting AIPS, you will get a menu showing
you all the alternative printers available. You should omit the PR option until you are familiar with the choices. The
OLD version of is likely to be relatively free of bugs (provided the version in NEW does not
prescribe format changes which prevent OLD from working), but the NEW version will contain improvements and
will be mostly debugged. The TST version is a debugging area recommended for NRAO staff and those few users
who may require the most recent software. (Note that this choice affects only the version of the AIPS program itself.
You may choose TST, NEW or OLD versions of the reduction programs at a later time — see
§3.5.)
2.2.4 Typing commands to the AIPS program
As of the 15JUL95 release, is available to users under a GNU-style license. This has numerous benefits, one
of which is that it allows us to incorporate other GNU-style code within our system. The first of these is the GNU
readline library which provides the user-input interface for AIPS under Unix beginning with the 15JAN96 release.
The GNU readline library gives the user the ability to use the cursor-arrow keys, as well as various “control”
and “escape” key sequences, to recall previously-entered commands, to edit the current command
line (without having to back-space and re-type the entire line), to search the command history for
previously-executed commands, to define customized key bindings for executing commands and macros, and
much more. The full information may be obtained with the command man readline from the system
command line (not inside AIPS). There is even “tab completion” based on the list of help files and
on context. At any point, when typing a symbol, you may hit the TAB key. The symbol name will be
completed if it is unique or the screen will flash (or the bell sound) is it is not. A second hit on the TAB
key will produce a list of the possible completions. Since a task name cannot be the first symbol on
a line, tasks are included in the possible completions only after some other symbol appears on the
line.
The default key bindings should be very familiar to users of emacs and/or the bash shell; many of them should also
be recognizable to users of the Korn and tcsh shells. Hard-core vi users can put AIPS into “vi-mode” and use
vi-like key bindings instead. (The basic emacs-like key bindings will be outlined below; it will be
assumed that those who are using the non-default vi-like key bindings already know what they are
doing.)
Your command-line history is automatically saved between sessions, unique to both the user number and the
“ number” of the session, and then recovered at the next AIPS startup.
Use of the GNU readline library for input can be disabled on a per-session basis by starting AIPS with the “norl”
option. This can prevent problems under some operating systems (most notably HP/UX) with putting
AIPS into the background, when running with input “fed” from a script, or when debugging AIPS
itself.
The key bindings are given below. Key sequences/bindings using the CONTROL key will be prefixed below with
“C-.” Those using the ESCAPE key (or “META” key — often available as the ALT key on PC keyboards and as the
“diamond” key on Sun keyboards) will be prefixed with “M-.” The basic cursor-movement key bindings
are:
C-b backward-character [also: left-arrow]
C-f forward-character [also: right-arrow]
C-p previous-command [also: up-arrow]
C-n next-command [also: down-arrow]
M-b backward-word
M-f forward-word
C-a beginning-of-line
C-e end-of-line
C-r incremental-search backward
C-p previous-history (move backward in history list)
C-n next-history (move forward in history list)
The basic editing key bindings are:
C-d delete-character (under cursor)
M-d delete-word (to right of cursor)
M-DEL delete-word (to left of cursor)
C-t transpose-characters (left with under cursor)
DELETE and BACKSPACE work as expected.