# Overview¶

MagAO-X applications are individual programs which control some aspect of the instrument, e.g. a hardware device or a software process. When an application starts, it is assigned an INDI device name, which is usually different from the executable file name. For instance, the pyramid WFS camera is controlled by the ocam2KCtrl process with device name camwfs. The command line to start this program is

[xsup@exao2 ~]$/opt/MagAOX/bin/ocam2KCtrl -n camwfs  Note that MagAO-X apps normally need to be run as user xsup. Each application runs in its own tmux session. This can be accessed (as xsup) using either tmux (tmux a -t camwfs) or using the xctrl utility: [xsup@exao2 ~]$ xctrl inspect camwfs


See xctrl for additional tools to control and monitor MagAO-X applications. To follow the log use the logdump utility:

[any-user@exao2 ~]$logdump -f camwfs  ## Configuring instrument applications¶ All MagAO-X applications use a common configuration system. In normal operations, the app configuration is read from a file located in /opt/MagAOX/config/ with the INDI device name and the .conf extension. E.g. camwfs.conf. The configuration files are basic TOML files, with key=value pairs, organized in sections: key1=value1 key2=value2 # this is a comment [section1] key1=value1 #this key1 is distinct from the key1 above, since it's in a section [section2] key3=1,2,3,4,5 #this is a vector or list  To see what the options for a particular application are use the -h options: [xsup@exao2 ~]$ /opt/MagAOX/bin/ocam2KCtrl -h.


An example from the output of that command is

-L --logDir                  logger.logDir             <string>        The directory for log files


which tells you that the short command-line option is -L, the long command-line option is --logDir, and the configuration file section is [logger] with keyword logDir. The value expected is a string. Finally, the description of this option is provided.

Though the configuration file specified by the -n option is the normal method to configure an app, additional settings can be made using the command line for troubleshooting and development. Use the -c option to specify an additional configuration file – any settings in this file will override the defaults (but anything not overridden will still be set by the default). Any options passed as command-line arguments will override any settings in the configuration files.

## Standard Options¶

All MagAO-X applications accept the following options:

Short Long Config-File * Type Description
-c --config config string A local config file
-h --help none Print this message and exit
-p --loopPause loopPause unsigned long The main loop pause time in ns
-P --RTPriority RTPriority unsigned The real-time priority (0-99)
-L --logDir logger.logDir string The directory for log files
--logExt logger.logExt string The extension for log files
--maxLogSize logger.maxLogSize string The maximum size of log files
--writePause logger.writePause unsigned long The log thread pause time in ns
--logThreadPrio logger.logThreadPrio int The log thread priority
-l --logLevel logger.logLevel string The log level
-n --name name string The name of the application, specifies config.

* In the “Config-File” column, the syntax section.keyword means that in the config file this option is set as follows:

[section]
keyword=value
`