The TCL interpreter divides the commands into a number of packages
each dealing with a separate set of operations.
The TCL system contains a mechanism for finding automatically
searching and loading new packages to if a command is used which
isn't in the currently loaded set. A dependency system allows
a package to require other packages to be present, so that for
example the FITS commands can arrange for the image commands to
be loaded.
To avoid the names of commands clashing with those in another package or with TCL's own internal commands they are prefixed with an abbreviation of the package name, so the command to rename an image is imrename.
Eventually TCL will support a namespace system to allow new commands
with the same name as an existing function, the command could
be resolved by giving priority to the last package loaded or by
switching the current assumed package. A fully qualified package
name similar to a full path could be used to unambiguously select
a particular command.
The purpose and commands in each of these packages are detailed in a separate section.
The image package contains the commands to handle image data.
The camera package manages the array controller. It contains functions
to initialise it and select the readout mode and paramters.
The system documentation is integrated into a help system using
html to display technical documents manual pages and context sensitve
on line help.
An interface to the astronomical FITS (Flexible Image Transport
System ) format allows images to be imported and exported and
manages the FITS header parameters.
The system must be able to issue commands to the telescope to
acquire new objects and request information back from the telescope
about it's current position.
The camera filter wheel is under computer control, this package
controls the selection of filter and the logging of which filter
was used for which exposure.
Created from $Id: package.htm,v 1.1 1997/03/05 18:28:08
mgb Exp mgb $