'$.Business.Letters.May .ToAlex'. If you wanted to move up a level (imagine the

tree diagram) you would have to give the command:

*DIR $.Business.Letters.May

However, the circumflex shorthand allows you to type:

*DIR ^

A similar effect can be achieved with the the *BACK command, which returns

you to the directory you previously selected, irrespective of where it was in the

hierarchy. This is not usually the same as *DIR ^ ,although you may like to try

and imagine the sequence of events which would lead to it being so.

The pathnames that *DIR accepts have a further feature, which is that you

may include the drive number in a pathname by preceding it with a colon (':').

For example to catalogue the directory $.GAMES on the disc in drive 1 you may

type:

*CAT :1.$.GAMES or, synonymously,

*CAT :1.GAMES (because the '$' is assumed automatically).

This means that you don't have to dismount your current drive and mount the

other just to look at or load files from it.

Creating directories

You can create new directories in the hierarchy wherever you wish. To do this

the *CDIR command is used; it should be followed by the pathname of the new

directory, e.g.:

*CDIR $.Letters.ToKitty

which will create a directory called 'ToKitty' in '$.Letters'. If '$.Letters' was

your CSD then you could equally use:

*CDIR ToKitty

Once you have created a directory you will need to 'move' to it, i.e. make it your

CSD, with the *DIR command. If you catalogue a new directory with *CAT you

will see it is empty of files, and it will remain so until you explicitly store some

there.

Libraries

There are three ways of executing machine code programs on the computer:

*RUN filename

*/ filename

*filename

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