disc contains. You can set the title of the CSD with the *TITLE command, but it

is set by default to the name of the directory. In the example the title is 'Main

disc'.

The Master Sequence Number is set to zero when the disc is formatted.

Whenever a file is saved into the directory, the MSN is increased by one and

this number is stored in the file's own sequence number entry (examples of

which may be seen lower down). The number allows you to get an idea of how

old a file is by comparing it with the files around it. Sequence numbers are reset

to 00 after reaching 99.

The second line of the listing gives information about the current drive. The

drive number is usually 0 or 1. The 'Option' tells the ADFS what to do with the

file !BOOT when the sequence is used (see the item concerning

*OPT 4 at the end of this section). The default setting is 'Off'.

Line three of the listing gives the names of the currently selected directory and

the currently selected library.

The remainder of the listing gives the names of the files in the directory, their

'access codes' and their individual sequence numbers. Access codes are

described in detail under the *ACCESS command below.

Detailed file information

The ADFS holds more information about each file than it displays when you

catalogue a directory. The *INFO command displays this extra information if

you follow it with the name of a file; it has a companion command, *EX, which

prints information on all of the files in the CSD or a named sub-directory.

The result of a *INFO command might look something like this:

Acorn DLR(03) 0001FE

RUBBISH LWR(09) 00000000 FFFFFFFF 00000EFE 00009C

Letters DLR(07) 00004A

The first part of the line is exactly the same as for a catalogue, but the latter

part is dependant on whether the named item is a file or a directory.

Files are followed by four items of information, each expressed in hexadecimal

notation; they are: the load address, the execution address, the length of the file

and its disc address. The load address tells the ADFS where to load the file in

memory, the execution address tells it where to start running the program once

it is loaded and the length is simply the number of bytes the file occupies. You

can print any of these values in decimal using BASIC, for example:

PRINT

to find the length of RUBBISH, above, in decimal.

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