WELCOME, and they in turn contain files of their own. In case you hadn't
noticed, this diagram mimics the directory hierarchy of the Welcome disc, and
you can use *CAT to see the contents of '$' for yourself.
When you first start up the ADFS, or issue a *MOUNT command, the '$'
directory automatically becomes the 'Currently Selected Directory' or CSD.
When you type *CAT the ADFS produces a catalogue of the CSD, but you may
instead request catalogues of other directories by following the *CAT command
with the name of a directory, e.g:
*CAT LIBRARY or
*CAT WELCOME
Using *CAT in this way only allows you to see what is in another directory; you
need to be more specific before you can load a file from a sub-directory because
normally the ADFS assumes you are looking for a file in your Currently
Selected Directory.
Earlier you saved a file called TEST in directory '$'. To fully specify where this
file is to be found we need to use its full name, or pathname. In the case of
TEST it is written '$.TEST'. The full stop is used to separate the filename from
the directory name, and you can use as many of them as necessary. Here are
some examples from the diagram above:
$.WELCOME The sub-directory 'WELCOME' in directory '$'
$.LIBRARY .PANEL The file 'PANEL' in directory $.LIBRARY
The CSD's name is assumed to prefix any filename that does not start with '$',
and you can include it explicitly in a pathname by using the symbol '@'.
Using the directory hierarchy
For directories to be useful you need to be able to 'move around' (i.e. change
your current directory) and to create new directories. The *DIR command is
used to change the CSD; for example either of the following commands will
make the root directory your CSD:
*DIR
*DIR $
In fact you can use pathnames of any length, e.g.:
*DIR $.LIBRARY.BASIC
Sometimes you may want to move to the 'parent' of your CSD, that is the
directory which contains it. You can do this by including the circumflex symbol
'^' whose similarity to an upward-facing arrow is not coincidental. Suppose
your CSD is deep down in a hierarchy, for example it has the pathname
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