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Last modified: December 2013

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AHELP for CIAO 4.9


Context: gui


GUI to run a task as a background process and display the output


taskmonitor <task to execute>


Taskmonitor is a graphical user interface (GUI) intended to allow another GUI application to run a task in the background but still display the standard error and standard output. Although designed to be launched from a CIAO GUI (e.g. peg or prism), it may be invoked from the command line and used as a stand-alone tool.

Taskmonitor takes a command to execute as input. Commands which contain white space or more than a single word must be enclosed in quotes. It executes the task as a background process and pipes the standard error and standard output of the task to a scrollable text window in the GUI. Since the task is run as a background process, there is no way for user input to be entered and thus should not be used to execute interactive programs. This means that CIAO tools may need to be run with "mode=h" set to avoid prompts for parameter values, as discussed in the examples below. Taskmonitor acts as a "dumb" terminal, which may influence the output of the program it is given to run.

The Analysis menu

The "Analysis" menu allows the user to run CIAO tools from taskmonitor. The configuration of this menu is described in "ahelp analysis-menu".

Example 1

taskmonitor ps

This example illustrates how taskmonitor may be used to execute a simple command and display the output. Since the command was a single word, quotes around the command are unnecessary.

Example 2

taskmonitor "dmlist mydata.fits opt=header,subspace mode=h" &

This example launches taskmonitor to run dmlist and display the header and subspace information for the file mydata.fits. By setting the mode parameter to 'h', the parameter interface's querying of auto-params is disabled, allowing parameter driven tools to be executed in a non-interactive mode. The & puts the taskmonitor process into the background to free up the shell it was invoked from so the user may perform other commands. Since the command to execute contained whitespace characters, the entire command was enclosed in quotes.

Example 3

taskmonitor "dmstat 'evt2.fits[sky=region(ds9.reg)][cols energy]' sig-"

Here we run dmstat on a filtered events file - restricting the calculation to only the energy column - and set the sigma parameter to no. The first parameter (infile) is quoted because it contains a space and note that we can still use shortcuts like "sig-" provided by the parameter library (see "ahelp parameter"). Since dmstat has only one automatic parameter, and this is specified in the command string, we did not need to set mode=h to stop for prompting of other parameter values.

Example 4

taskmonitor "ahelp -b PARAM dmstat" &

Here we run the ahelp tool to display just the PARAMETER section of the dmstat ahelp file. Since taskmonitor acts like a dumb terminal there is no ability to control the output as there is at the command line, although you can use the scroll bar to view all the text.

Example 5

taskmonitor "ahelp -n 130 -b QEXAMPLELIST aconvolve" &

Similar to the previous example but this time we pass several options to the ahelp command.


There are no known bugs for this tool.

See Also

analysis-menu, gui, peg, prism

Last modified: December 2013
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