Z.1 NRAO workstations — general information

All NRAO workstations run some version of the Unix operating system, Linux on PCs and SunOS (Solaris) on Suns. Unix systems are intrinsically sensitive to the difference between upper and lower case. Be sure to use the case indicated in the comments and advice given in the following notes.  itself is case-insensitive, however; conversion of lower-case characters to upper-case occurs automatically. (Unix systems have a variety of characters for the prompt at monitor (job-control) level, and allow users to set their own as well. We will use $ as the prompt in the text below.)

Z.1.1 The “midnight” jobs

The versions of  on all NRAO Sun, SGI, DEC, and PC systems are kept up to date continually with the master versions on the Charlottesville Sun called kochab. This is achieved by automated jobs that start running at very antisocial hours of the early morning. Any changes formally made to the TST version of  are copied to the relevant computers and recompiled/relinked. Midnight jobs run in Charlottesville, Socorro, Green Bank, Tucson, and at several other sites around the world.

Z.1.2 Generating color hard copy

Z.1.2.1 Color printers

Color printers are, these days, simply printers that understand the color extensions to the PostScript language used to describe plots. The NRAO owns two Tektronix Phaser 560 color printers, one in Charlottesville and one at the AOC in Socorro. You may display your PostScript file on the printer in Charlottesville simply by typing

The paper size is 8.5 × 11 inches, which is the default for  tasks TVCPS and LWPLA. To have the file printed on transparency paper use queue ps1tektran rather than ps1tek560. Full control over this complex printer is available with the multiprint command; type multiprint --help  C R for information. At the AOC, the queue names are pscolor and psoverhd. If you do not wish to save the plot as a disk file, you may also print it directly from within . The color printer is one of the printer choices when you start up AIPS, but you probably want to select a regular PostScript printer as your default printer. You can change your printer selection with the verb PRINTER; use PRINTER 999  C R to see what your choices are and the PRINTER n  C R to choose the printer numbered n.  print routines will re-direct PostScript files that actually contain color commands to the first PS-CMYK printer in the list, but will not re-direct ordinary print jobs to some printer other than a color printer. There are some special instructions for the color printer at the AOC in §Z.3.7.

Z.1.2.2 Software to copy your screen

To obtain a color hardcopy of what is on your screen, there are three software options you can choose. These are TVCPS, xv, and xgrab. Having created a PostScript file, you can print it on color printers at the NRAO or copy the file via e-mail or scp, rcp, or ftp to some other site for printing.

The TVCPS task in  will create a color Encapsulated PostScript file from whatever is displayed on the  TV server (XAS). If you use the OUTFILE adverb, this file is saved with whatever name you specify (see §3.10.1). If you specify a black-and-white output to TVCPS, then the output can be sent to any PostScript printer. Color PostScript must be sent to pscolor or the Solitaire. You can, of course, edit the save file (if you are a PostScript wizard) and can insert the file (since it is encapsulated) in another document. See the Charlottesville Workstation Guide for a short chapter on PostScript

The xv program is a Unix utility program available on most systems at the NRAO. It is mainly intended for image display of GIF, JPG, TIFF, and other format files. When you start xv, click the right button mouse anywhere in the xv window to bring up the control window. One of its features is a screen grab which is controlled by the “Grab” button in the lower right corner of the control window. Before you press this, arrange your windows and icons so that you can see exactly what it is you want to grab (e.g., the XAS server). Now press the “grab” button. The bell will ring and the cursor will change to a white cross symbol; move it to the top left of the area you want to grab. Then press and hold down the left mouse button, and drag the mouse cursor until it is at the bottom right of the area you want to grab. As you do this, you will see a box pattern on the screen outlining the area selected. Once you are done selecting the area, release the mouse cursor. When xv has finished grabbing the screen, it will beep twice, and whatever you grabbed appears in the main xv window. You can now use the “save” button of the control window to save this as any format you want. Once nice feature of this is the “save as Postscript” option. It allows you to scale, rotate, and position the image in relation to the page. Its user interface is better than most image utilities.

Finally, the xgrab program provides similar functionality to the “grab” feature of xv, with fewer output formats but much more control over how the grabbing is done. By default it allows three seconds in between starting the grab and when it actually starts to read the screen; this can be useful for setting things up. Also, it un-maps itself from the window when grabbing so you don’t have to worry about getting it out of the way. Unfortunately, there appears to be some problems with its encapsulated PostScript output.

Z.1.3 Color film recorders

The NRAO used to own two Solitaire film recorders, one in Charlottesville and one at the AOC in Socorro. Both have now been decommissioned. You are likely to find commercial services in any good-sized town to take PostScript files on floppy or zip disk to convert into slides.

Z.1.4 Gripe, gripe, gripe, …

Each week, one of the (few) members of the  group is the so-called “designated AIP.” It is this person’s job to assist local and remote users with their  problems. Often this person will provide advice or simple fixes to bugs, while more complex problems may be passed off to the person in the group who understands that area best. Contact the designated AIP (and all members of the group) at the e-mail address daip@nrao.edu.

Suggestions and complaints entered on all computers with the GRIPE verb (see §11.1) are sent immediately by e-mail to several addresses in the  programming group, including daip. The most urgent are addressed and, sometimes, answered. All gripes were entered into a database which resides on zia.aoc.nrao.edu. Users may read the contents of this database in as much detail as they can stand. To do so, login to the account called gripe on zia. This is a “captive” account, requiring no password, and allowing you only to execute an especially prepared version of the text editor emacs. When you tire and exit the special emacs, you will be logged out of zia. Note that this system has not been maintained in recent years due to the decreases in manpower and increases in the use of e-mail and direct computer connections.

After you log in, you will be presented with a selection/options menu. Fill in and/or alter some of the selection criteria to limit which gripes you will view. Then, select display option index, and, only when you are fully ready, hit a  C R. You will be shown a descriptive list of the selected gripes. If you wish to read one of them in detail, move the cursor to it and hit  C R. The space bar gets you the text of the next gripe and typing the letter q returns you to the index. Another q returns you to the selection/option form. Typing a ? in any of the displays will provide you with information on all the options available at that level of the system.

 Memo No. 88 describes the system in some detail. This memo may be available on your  system as file $AIPSPUBL/AIPSMEMO88.PS in PostScript form. It is also available to the “World-Wide Web” (start with “URL” http://www.cv.nrao.edu/aips/aipsdoc.html) so that it may be examined and retrieved over the Internet. The file used is also available via anonymous ftp on host kochab.cv.nrao.edu as a PostScript file named /pub/aips/TEXT/PUBL/AIPSMEMO88.PS.

Z.1.5 Solving problems at the NRAO

Below are details specific to the Charlottesville and Socorro systems for handling some of the problems which may arise in .

Z.1.5.1 Booting the workstations

Modern workstations, especially the powerful Suns and PCs, are complex Unix systems which may have remote users within the NRAO and guests from elsewhere on the Internet. Users should never attempt to boot the system on their own. If the machine appears to be dead, find or call one of the people listed on the bulletin boards in the  Caige for this purpose.

Z.1.5.2 Printout fails to appear

Check the  output messages that appeared shortly after you submitted your print job, whether it be from PRTMSG or LWPLA, or some other task. You should see the output of the Unix command to show the printer queue status. If anything went wrong with the print submission, an error message should be obvious. If not, check the output of the lpq (or lpstat for Solaris 2.x) command, see what print queue was involved, and check it again from the Unix command level (not from inside AIPS).

AIPS will delete spooled files about 5 minutes after they are submitted. If the print queue is stalled (due, say, to a jammed printer) or backed up with a lot of jobs, it is possible that the file was deleted before it was gobbled up by the print spooler. This time delay has been made a locally-controlled parameter, so it is possible to set it to values higher than 5 minutes. At this writing, the Charlottesville systems are using a 20-minute delay time.

Finally, check to see if the printout was (a) diverted to the “big” printer (psnet in room 213 at the AOC or ps3dup in the Charlottesville library) because it was too long for the smaller printers, (b) you forgot which printer you had selected on aips startup, or, at the AOC, (c) someone has taken the output and filed it in the “today” file bin (at the AOC this is on the left side of the post directly behind the psnet printer).

Z.1.5.3 Stopping excess printout

To find out what jobs are in the spooling queue for the relevant printer, type, at the monitor level:

or to display a specific queue

where ppp might be psnet at the AOC or ps3dup in Charlottesville. If the file is still in the queue as job number nn, you can type simply

lprm and cancel will announce the names of any files that they remove and are silent if there are no jobs in the queue which match the request.

Unfortunately, it is now very difficult to stop long print jobs. The large memories of modern printers mean that more than one print job can already be resident in the printer while your long unwanted job is being printed. Therefore, turning off the printer is not an option. Try to be more careful and not generate excess printout in the first place (save a tree).

A nice option available for most  print tasks or verbs is adverb OUTPRINT which allows you to divert the output to a text file. Then you can use an editor like emacs to examine the file in detail before printing. The Unix command wc -l file will count the number of lines in a text file called file for you; note that -l is the letter ell, not the number one.  provides a “filter” program to convert plain (or Fortran) text files to PostScript for printing on PostScript printers. The command

will print text file file on PostScript printer ppp. The parameter nn is the number of lines per page used inside ; it is likely to be 97 if direct printing comes out in “portrait” form or 61 if the direct print outs come out in “landscape” form.

It is not unusual for  jobs to be in the 1 Mbyte or more in length, which will take 5–10 minutes to print. For large text files, it is quite likely that the ZLPCL2 shell script will divert the job to a “big” printer (in Socorro, lp27 in room 213). However, graphics files are not subject to such restrictions.

If you plan on generating large or very complex plot files which you intend to print, please select the psnet printer at the AOC or the ps3dup printer in Charlottesville. Since they are, effectively, on the ethernet, the bandwidth to it is usually an order of magnitude faster than any serial line. You — and others — will have to spend less time waiting for jobs to come out of the printer. If you are submitting jobs which you know are several Mbyte in size, we ask that you wait until after local business hours to avoid tying up the printer.

Z.1.5.4 CTRL Z problems

The last process placed in the background via CTRL Z can be brought back to the foreground by typing fg  C R in response to the monitor level % or $ (or whatever) prompt Alternatively, the user can type  jobs  C R, which displays all background processes associated with the current login and can bring a specific process to the foreground by typing fg % m  C R, where m is the job number as displayed by the jobs command as [m]. For example, if a user initiated his AIPSn by typing aips new pr=4 C R and:

Z.1.5.5 “File system is full” message

The message write failed, file system is full will appear when the search for scratch space encounters a disk or disks without enough space. This is only a problem when none of the disks available for scratch files has enough space, at which point the task will shut down. Use the BADDISK adverb to avoid disks with little available space.

Z.1.5.6 Tapes won’t mount

Occasionally, both local and remote tape mounts may not work successfully. The source of the problem is often your failure to load the tape physically into the device or to wait until the device is ready to read the tape. DATs and Exabytes, in particular, go through lots of clicking and whirring before they are really ready. An error message like AIPS 1: ZMOUN2: Couldn’t open tape device /dev/nrst0

(or some other tape-device name gibberish) is to be expected in this case.

If you attempt to mount a remote tape and get the messages: AIPS 1: ZMOUNR: UNABLE TO MOUNT REMOTE TAPE DEVICE, ERROR 96 AIPS 1: AMOUNT: TAPE IS ALREADY MOUNTED BY TPMON

it means that your AIPS and the tape dæmon that you are using disagree on whether the tape is already mounted in software. The most probable reason for this is that you are attempting to mount someone else’s tape (check your inputs and the labels on the device closely) — or that the previous user of the device dismounted the tape from the hardware but neglected to do it from software. In this case, you have two choices: (1) find the culprit and have him do a software dismount, or (2) find an  Manager to kill the confused dæmon and restart it. (If you are using tape device n on computer host_name, then you need to stop the process called TPMONm, where m = n + 1 on computer host_name and then start it again by running /AIPS/START_TPSERVERS on that computer. This should be done by an  Manager.)

If you attempt to mount a remote tape and see, instead, the messages: ZVTPO2 connect (INET): Connection refused AIPS 1: ZMOUNR: UNABLE TO OPEN SOCKET TO REMOTE MACHINE, ERROR 1 AIPS 1: ZMOUNT: ERROR 1 RETURNED BY ZMOUN2/ZMOUNR

then the tape dæmons are not running on the remote machine. Log into the remote machine as user aips and type: /AIPS/START_TPSERVERS

After a minute or two, you should see some messages from STARTPMON about starting TPMON dæmons. Alternatively, you could exit from AIPS and start back up again, including tp=host_name on the aips command line; see §2.2.3. If the tape still doesn’t mount after doing this, see the  Manager.

Z.1.5.7 I can’t use my data disk!

If at some point during your work you find you are prevented from reading or writing files on a data disk, it could be that your  number does not have access to that area. If you encounter the message: AIPS 2: CATOPN: ACCESS DENIED TO DISK 8 FOR USER 1783

it means that user 1783 has not been given access to write (or read) on disk 8. This can be seen, in the AIPS session, by typing FREESPAC to list the mounted disks. If you see a data disk listed with an access of Not you, it means your  number has not been enabled for that disk. If you feel that you should have access to that particular disk, see the data analysts (at the AOC) or an  Manager about enabling your user number.