3.2 Your AIPS message file

AIPS and all tasks talk back to you by writing messages to a disk file called the “message file” and/or by sending them to you on the appropriate “message monitor.” Simple instructions and progress messages usually go only to the monitor; very few (if any) messages go only to the file. For AIPS itself, the message monitor is always the workstation window or terminal into which you are typing your commands. For the tasks, the monitor can also be a separate terminal (on well-equipped, but old, systems) or a second workstation window under control of the AIPS dæmon process MSGSRV. You can control whether or not you get the message server window by the setting of a Unix environment variable (AIPS_MSG_EMULATOR). Enter


for details.

At most AIPS installations, you get a message server by default. You may also control the size and appearance of the message server with parameters in the X-Windows .Xdefaults file. These parameters are also listed in by HELP  MSGSRV  C R.

You may review the contents of the message file by typing PRTMSG  C R at the > prompt at your terminal. PRTMSG is an example of an AIPS “verb” — it does not need a GO from you to execute, and it is not shed from your terminal. Each message in the file has, associated with the text, the time, task name, POPS number, and the priority of the message. The priority codes range from 0 for user input to 2 for “unimportant” messages to 5 for “answers” and other significant normal messages to 8 for serious error messages. The PRTMSG verb has adverbs to let you select either the printer or your window or terminal for the display and to let you control which messages will be displayed. For example, to set the minimum priority level for messages to be displayed, type:


where np is the desired minimum level,

before running PRTMSG; then only messages at this level or above will be listed on the printer or terminal. If np is 5, then messages at level 0 are also shown. PRTMSG has further adverbs to limit the output by program name (PRTASK, uses minimum match), message age (PRTIME as upper limit to the age), and AIPS number (PRNUM). Note that PRNUM must be your AIPS, i.e.POPS, session number, not your user identification number. The choice of the output device is made with

> DOCRT  -1  C R

to select the line printer or a text file under control of OUTPRINT.

> DOCRT  1  C R

to select the terminal at its current width 72 characters

> DOCRT  nc  C R

to select the terminal at width nc characters: 72 nc 132.

The wider you can make your window display, up to 132 characters, the more information AIPS can put on a line. You may change the line printer selection with PRINTER. If the line printer is selected (DOCRT=-1; OUTPRINT=’’), PRTMSG will ask for permission to proceed if more than 400 lines will be printed.

PRTMSG does not delete messages from your message file. Use:


to delete messages and to compress the message file.

CLRMSG supports adverbs like those of PRTMSG, except that the deletion is of messages older than PRTIME and the printing is of messages younger than PRTIME seconds ago. Old messages are automatically deleted from your message file when you EXIT from AIPS. (The time limit for “old” messages is set by your local AIPS Manager. Usually, it is about 3 days.)