2. Getting Started
------------------

This chapter describes the basics of logging into a computer account
starting up UniPOPS and arriving in the program with the set-up of 
your choice. It also details how to exit the program, and log out 
of the computer.


2.1 Your Computer Account
-------------------------

The way computer accounts are created and managed differs from site
to site.  The following attempts to describe both the Green Bank
and Tucson policies concerning the creation of accounts.  Since
these policies may change, you should always consult the local
staff for the most up to date information.  These policies also
differ from site to site.  For example, in Tucson observers share a 
common account (the "obs" account) and are given different subdirectories 
for their use during an observing run.  In Green Bank, users are given 
their own accounts for using while observing and reducing data.  

When your observations appear on the schedule for the Green-Bank
140-foot telescope, the System Administrator will ensure that you have
a computer account. If you, or one of your collaborators, already have
an account on the Green-Bank Suns, you will probably use that account
during your stay. Otherwise, a new account will be set up in the name
of the principle investigator on the observing proposal.  If, on
arrival at Green Bank, you should be confused by the computer system,
or believe that you have slipped through the `net' and have no computer
account, ask the System Administrator, or the Friend-of-the-Telescope,
about your account and they will set up a new account.

Shortly before your observations are to begin at the 12-meter telescope
on Kitt Peak.  A subdirectory in the "obs" account will be created
and initialized for your use during your stay at the 12-meter.  Your
initials are typically used as the name of this subdirectory.  The
telescope operators can create this subdirectory if none exists
for you when you arrive at the site.

At both sites, UniPOPS can be used to process data on any of the
observatory's Sun workstations. There is a minor difference between the
Sun at the 140-foot telescope, and all other Green-Bank Suns, in that
the disk on the machine at the telescope holds the master on-line data
file (see Section 2.2).


2.2 Logging In and Starting-Up UniPOPS
--------------------------------------

You are recommended to run UniPOPS directly from a Sun workstation,
although you can run the program from either a dumb terminal, (albeit
without graphics and many other useful features), or a Tektronix 4014
terminal or emulator.


2.2.1 Logging In
----------------

When you first sit before the terminal, you should get the computer's
attention by striking a <CR> (i.e. a carriage return). When prompted,
you should enter the account username plus a <CR>, followed by the
correct password (if yet set), and a further <CR>.  For users at the
12-meter, you should obtain the current password for the "obs" account
from the telescope operator.  Each time you log in to the "obs" account,
you will be asked for your 3 initials (the same initials used to
create your subdirectory).  It is vital that you enter these initials
correctly or you will not be able to access your on-line data.  You
should always verify that you are in the correct subdirectory before
continuing.  If you suspect that you are not in the correct subdirectory,
you should log out of the account and start over.  If you continue
to have problems while logging in, report them to the telescope operator 
or another member of the 12-meter staff.

When you log in for the first time at either site, the computer will ask 
a series of questions. At present, the series consists of just one request, 
namely, "Which of a range of editors do you wish to make your default 
editor ?" If you are operating from a Sun workstation, we recommend that 
you choose the Sun screen editor, (textedit), unless you are more familiar 
with an alternative (e.g. vi, edt, emacs).  Select an editor from
the list that you have just been shown.  At this point, you should
see "preparing directory - be patient ...".  Your directory is
being prepared so that you can use UniPOPS.  Specifically, you are getting 
empty data files for LINE and CONDAR (LDATA, LKEEP, LSAVE, etc), copies of 
the UniPOPS memory files (LMEMORY, CMEMORY), a default setup file 
(12-m only) and a .unipops file that contains the settings of various
variables that control the behavior of UniPOPS.  The default values found 
in the .unipops file should be adequate for new users while experienced 
users may wish to change it's contents (see Appendix M).

All other things being equal, it is preferable that you operate from
the `windows' environment of a workstation for UniPOPS to work most
affectively.  However, if you are working from a dumb terminal or a
Tektronics 4014 terminal, there is no `windows' facility available, and
after logging in you will be left at the normal UNIX command line.
When using a dumb terminal, you can continue to log in to UniPOPS and
work with your data, but you will not be able to display your data
until a workstation or a Tektronics 4014 is available.  Graphical
display is possible with the Tektronics 4014, although both text and
graphics share the one screen. Slight differences on starting-up
UniPOPS from the different terminals will be highlighted below.

If you are sitting before a Sun workstation and have successfully
logged into the computer, it will start to bring up its windowing
environment. A short description of possible window environments is
given in Appendix C, "Window Systems", of this Cookbook and we urge all
first time users to read that Appendix before proceeding further. For
the rest of this Cookbook we assume that you are using either the
X-Window or SunView window system.  At one point early in this login
sequence for Green Bank users, the computer will pause and give you five 
seconds to hit a <Ctrl-C> should you not wish to enter the `windows' 
environment.  The `windows' environment that appears probably will then 
consist of open CmdTool windows (one being the Console window), plus 
icons representing a clock, a MailTool and further CmdTools.

(For the benefit of users who are not familiar with UNIX, but wish
either to perform normal computing outside UniPOPS, or to send commands
to the system from inside the program using the UniPOPS command SYSTEM
-- see Section 12.1 -- we give a summary of the most-used UNIX commands
in Appendix B, at the end of this Cookbook.)


2.2.2 Setting a Password
------------------------

New accounts in Green Bank are created with no password or a default 
password supplied by the System Administrator.  We STRONGLY RECOMMEND that
observers set a password for themselves the very first time that they
log in.  User at the 12-meter MUST NOT change the password of the
"obs" account for obvious reasons.  To change the password of an
account place the cursor in a CmdTool window (preferably not the Console 
window, as this is where the system will sometimes print messages) and 
type either the command 

		% yppasswd

or

		% passwd

[Ask the system administrator which you should use].  On pressing <CR>,
the computer will prompt you for the password of your choice.  Note
that at some sites you should NOT use the UNIX `passwd' command, as
this will set your password only on the Sun that you are logged in to,
and will not export it to the rest of the LAN !


2.2.3 Starting-Up UniPOPS
-------------------------

If you are sitting at a Sun workstation, we suggest that you start-up
UniPOPS from a CmdTool window that is NOT the Console window as that
window will be used by the system to display messages.  Start-up
UniPOPS by typing one of the following commands at the UNIX % prompt: 

	--------------------------------------------------------
	| Program Name	|  Type of Data   |	Where          |
	|---------------|-----------------|--------------------|
	| gbline        |  Spectral-Line  |   	Green Bank     |
        | tucline	|  Spectral-Line  |     Tucson         |
        | cvline	|  Spectral-Line  |     Anywhere else  |
	|		|		  |		       |
        | gbcondar	|  Continuum	  |     Green Bank     |
        | tuccondar	|  Continuum	  |     Tucson         |
        | cvcondar 	|  Continuum	  |	Anywhere else  | 
	--------------------------------------------------------


(NOTE that the gb, tuc, and cv versions of LINE and CONDAR are
identical, except as to which on-line data files they access. CONDAR
and LINE are themselves identical, except for a handful of specialized
commands and the type of data. Throughout this Cookbook, a reference to
CONDAR or LINE, implies the local -- i.e. gb, tuc, or cv -- version,
while UniPOPS implies either LINE or CONDAR.)

During the UniPOPS start-up sequence, a LinePlot or ContPlot icon will
appear on the screen, which represents the graphics window in which
your plots will appear. The program will also request you to enter a
few pieces of information,

  a) The first time you log in to UniPOPS, a series of messages will
     appear containing news items concerning recent changes made to the
     program and messages from the programming staff. On subsequent
     log ins you will be shown a list of the current news items. To
     read any of these, enter the name of the item when prompted, or
     <CR> to proceed.

  b) You will be asked whether you wish to recover the UniPOPS
     environment from the last time you ran the program ? You may
     answer Y or N for "Yes" or "No" respectively, while just a <CR>
     will give the default of N. (You will not be asked this if it is
     your first run of LINE or CONDAR.)

  c) Unless you are logged directly into a Sun workstation, and are
     running UniPOPS in the window environment on THAT workstation,
     you will now be asked what graphics capability your terminal
     possesses. Answer from the table of options displayed. Unless you
     have a standard printer defined at login (see Appendix M), you will 
     also be asked which printer you wish to use.  Again your answer should 
     be from the displayed table of options.

  d1) If you will be using UniPOPS to reduce 140-foot telescope data via
     gbline or gbcondar, you will be requested to supply the project
     code for your observations. This should be identical to the code
     you specified in your observing file.  If you specify a project
     code of 'null' then all your requests for on-line data will be
     ignored.

  d2) If you will be using UniPOPS to reduce 12-meter telescope data
     and you are at the telescope, you will be shown a list of default
     on-line data files.  These will be the highest versions of each
     file type for your initials (which you entered when you logged in
     to the workstation) found in the default data area.  If you wish
     to change the version numbers, you should use the CHNGONLINE or
     CHNGVER verbs after these initialization steps have been
     completed.

     There is currently no remote data access for 12-meter on-line data.

  e) Finally, you will be shown the currently accessible data and disk 
     files.  These are either default files or files you last used
     in a previous UniPOPS sessions [if you had saved your environment
     and have recovered it by answering Yes in step b) above].  

     After startup is completed, you can use the CHNGFILE verb to
     change which files you want UniPOPS to access (see Section 5.3).  

  f) If you answered 'N' to the question described in b) above
     concerning `recovering' your UniPOPS environment, then the final
     action by the program when logging-in to UniPOPS is to look for a
     file called LSETUP for LINE or CSETUP for CONDAR, containing
     UniPOPS instructions.  This file can be used to tailor the UniPOPS
     session to your convenience.  For example, suppose that a file
     yy.prc exists in the log-in disk area containing a procedure (see
     Chapter 13) that you need in every UniPOPS session, then this can
     be made immediately available by editing into LSETUP the
     instruction,

	BATCH yy.prc

     which will automatically install the procedure at log-in (see
     Section 13.9 for a description of the BATCH command.)

     The commands in the setup file are executed silently (i.e., you'll
     not see the contents of the setup file as they are being read and
     executed but you will see any generated error message).

     The default setup files for 12-m users are either CSETUP.12meter
     and LSETUP.12meter (for CONDAR and Line users, respectively).
     The setup files that were created for you when you first logged into
     your subdirectory in the obs account contain commands to BATCH
     in these default setup files.

     No default setup files are available for Green Bank observers.  


If you are running UniPOPS from a Sun workstation, you should now open
the LinePlot or ContPlot icon and, if required, reposition the
resultant graphics-display screen.  See the Appendix C for information 
on how to open, move, and resize windows.  


2.3 The UniPOPS Prompt
----------------------

Now that you are logged into UniPOPS, the program prompt should appear.
The default prompt is,

	Line > 

     or 

	Condar > 

You can change this by setting the string that you desire to use as
the prompt into the 8-character UniPOPS string adverb (see Sections
3.2.2 and 3.3) PROMPT.  Trailing blanks in the adverb PROMPT will not
appear in the screen prompt.  For example to set the prompt to the
string, 'HI >', type,

	>PROMPT = 'HI >'

At the 12-meter, the prompt is used to indicate what the default
on-line data file type is (for filter bank data, the prompt is
"LineF>" while for hybrid spectrometer data, the prompt is
"LineH>" and for Condar, the prompt is as stated above).  This
prompt is set by the two standard 12-meter procedures, FBDATA and
HCDATA.  At startup (in LSETUP.12meter, the default setup file),
FBDATA is executed and the default prompt is therefore "LineF>"
We recommend that you NOT change the prompt while observing at
the 12-meter.  See the documentation on FBDATA and HCDATA for
more information.

NOTE : In this Cookbook, the examples given will assume that the prompt
is '>',



2.4 Possible Snags during Start-up 
----------------------------------

Appendix F, at the end of this Cookbook, lists the full set of UniPOPS
error messages, and can be consulted when problems arise. However, on
start-up the most usual snags are,

  .  If you last left UniPOPS `explosively', then a `lock' may well
     exist on your files. This has to be cleared before the program can
     be started up successfully. If one attempts to start-up UniPOPS in
     this condition, it will inform you of the presence of the lock, 
     and give you the following 3 options:

	To exit the program, type: 0
	To remove a leftover LOCKFILE, type: 1
	To ignore the LOCKFILE, type: 2

     If you are sure that the LOCKFILE exists because you last left
     UniPOPS `explosively' (i.e. in a non-standard way, without using
     EXIT successfully), then you should type "1" to indicate that the
     program should remove the offending LOCKFILE.

     However, BEWARE, as a lockfile will also exist on your files if your 
     collaborator is already running UniPOPS from the same account and 
     directory, and you may create a disastrous conflict if you clear that 
     lock.  Or, you may have left UniPOPS running on another terminal
     using the same directory and forgotten about it.  In both cases,
     the LOCKFILE really does indicate that someone else is using the
     program.  The program will show you who created the LOCKFILE and
     when and where it was created.  You should use that information
     to determine what the likely cause of the existence of the LOCKFILE
     is and take appropriate action.  See Appendix F for a further
     discussion of this problem and the implications of ignoring 
     the LOCKFILE.

  .  Suppose you have been away from the observatory for some while, or
     have had your version of the UniPOPS program replaced by the
     latest upgrade, UniPOPS may indicate on start-up that the memory file, 
     or recover file, and the program versions are not compatible.  You will
     then be offered the following choice:

	Do you want to recreate your memory file :
        (y or n) ? [ default :n ]:

     If you choose "n" the program will exit.  One possible cause of
     a missing memory file or a memory file with the wrong access
     privileges is attempting to start up the program from an
     incorrect subdirectory.  It is probably a good idea to understand
     why your memory file is out of data or does not exist before
     answering "y" to the above question.


NOTE : If the recover file is out of date, you will be told so by the
program which will continue.  You will not be allowed to recover from
that file.  There is usually no way to recover the information in an
out of data recover file except to hope that you can use an older version
of the program that can read the recover file.


2.5 Logging Out
---------------

Before exiting UniPOPS, think if you need to STORE a copy of the
program memory (see Section 13.10). When you are content that you are
really ready to exit the program, do this by typing at the UniPOPS '>'
prompt,

	>EXIT

Before returning you to the operating system, EXIT will first ask
whether it should update the `recovery file'. Answer either Y or N for
"Yes" or "No" respectively, as there is no default.  If you choose to
update the file, then next time you use UniPOPS you can tell the
program to read in the recovery file that has just been saved.  This
will recreate the exact environment of the present analysis session
apart from the two- and three-dimensional facilities described in
Chapter 16.  

After exiting from UniPOPS, you should exit the windowing system (if you are
using one).  See Appendix C for details.

You can now log-out by typing, at the UNIX % prompt,

	logout

If this doesn't work, try,

	exit

     or 

	bye
