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The Backer Version 1.7D
A Hard Disk Backup Utility
for the
Commodore Amiga
June, 1988
Copyright (C) Dexter (Chip) Orange, 1988.
The Backer is a program for backing up your Amiga hard disk as quickly and as
easily as possible. There are other good public domain back up programs (such as
MrBackup) which you could use, but I've never come across any that have what I consider to be a critical
feature of a good backup program: the use of the AmigaDOS Archive bit
of the file protection bits. This bit is supposed to be used to indicate whether a file has been backed up yet or not,
but no PD backup program I've seen makes any use of it. The idea is very simple:
when ever AmigaDOS creates/modifies a file it clears the Archive bit. Periodicly you can backup the files
which have cleared Archive bits and after each is backed up, you set its Archive bit.
This makes doing incremental backups very easy.
Backer also comes with a utility (ArchStatus) which allows you to view/set/clear the Archive bits
for a drive/directory/file manually. (documented separately).
Using The Backer:
The syntax of the Backer command is:
Backer [<source>] [NEW|ALL] [SET|NOSET] [PREFIX <prefix-string>] [FORMAT <drive>]
[ERRORS <file>] [LISTING <file>]
Where:
<source> is the drive/directory/file to be backed up,
NEW/ALL indicates whether to backup only the new (Archive bit not set) or all files,
SET/NOSET indicates whether the Archive bit should be set after copying the file,
PREFIX <prefix-string> allows you to specify what the backup disks will be named.
FORMAT <drive> tells Backer to prompt you for a new disk in the specified
drive each time one is needed, and for it to do the formatting.
ERRORS <file> is a file/device where an error report should be written
LISTING <file> is a file/device where a backup listing should be written
(Note that if you don't want a error/backup listing, you will have to do:
ERRORS NIL: LISTING NIL:)
Defaults: <current drive> NEW SET PREFIX <todays date> ERRORS <prefix>.ERRORS LISTING <prefix>.LIST
Backer will begin to copy the files you have specified with <source> which
meet the condition you specified with the NEW/ALL parameter to floppies
(note that it preserves the file creation/modification date).
(Also note that even though floppies are constantly refered to here as the
backup media, you can actually use any device which is capable
of being accessed like a disk drive.)
The floppies will have names of the form <prefix-string>.n
where n is a sequence number beginning with 1.
The copying process is much faster than the standard DOS copy, but this is at
the expense of memory. Backer attempts to use all the memory available, so
if you want to do something while backer is working, start that something up
first so it can allocate the memory it needs before Backer pigs it all up.
You will be prompted to put volume "<prefix-string>.1:" into any drive,
so you should either have enough pre-formatted disks labeled as <prefix-string>.1 ... <prefix-string>.n
on hand, or run backer in its own CLI window so you can format disk N+1 as Backer is copying to disk N,
or use the FORMAT <drive> option to have Backer do the formatting for you.
You can use another utility supplied with Backer called Estimator (documented separately)
to calculate how many disks you will need ahead of time.
In order to make the most efficient use of floppies, Backer uses a
"best-fit" algorithm for the storage of files on floppies. This basically goes like this:
If you have a file about to be backed up and find it won't fit on the floppy, instead of
just asking for another floppy (the current one will likely have plenty of room still left on it),
save this one til later and find another file that will fit. The consequences
of this is that, Backer (with a usual mix of large and small files) will
fill most disks to at least 98 % of their capacity. The downside is that this
can scatter files which are in the same directory to many different backup disks, making
the retrieval of a single specific file a little time consuming without a listing.
Examples:
To do a full backup:
(use The Estimator to determine how many disks you will need)
1>ESTIMATOR DH0:
(if you have a two drive system you can be formatting disks 2 through
n from a second CLI while Backer is using the previous disk)
(now begin running backer in the background so you can be doing something useful
in the mean time)
1> RUN BACKER DH0: ALL
(Note that the prefix defaults to todays date such as
19-Mar-88)
(To perform an incremental backup (I do one at least once a week),
modify the above slightly by specifying the "NEW" parameter on the ESTIMATOR
command, and by replacing the "ALL" parameter on the BACKER command with "NEW")
Restoring:
Backer creates its backup files with the same AmigaDOS directory structure that they had, so restoring is a breeze.
You can either simply
insert the backup volume you wish to restore from and then copy it in its entirity to your hard disk:
Copy <prefix-string>.1: DH0: all
will put all the files back just as they were. Since everything is in AmigaDOS file format,
you can easily search the backup disks to find a particular file and then copy it to your hard disk.
Alternatively, you can use another program supplied with Backer called The
Restorer. It has several advantages over
DOS copying such as preserving the file date, setting
the archive bit for the restored file, and unless
specificly directed to do so, it will not copy over any file with a date
greater than that of the backup file (The Restorer is documented separately).
Future Features:
if you have any suggestions or bug reports you can reach me at:
Home: (904) 877-0061
Work: (904) 487-2680
CompuServe: 71450,1162
U.S. snail:
3227 Rain Valley Ct.
Tallahassee, FL. 32308
Here are some of the things I plan to add:
O An index to files backed up so that the disk
containing a particular file can be identified immediately.
O Amiga style wild cards for file specifications
(currently you can only specify a drive/directory/file as the <source>)
O Date ranges for file specifications
O The ability to specify a list of files which are to be excluded
from the backup.
(currently the only way to exclude certain files is to use the ArchStatus
utility to set their archive bits, and then do an incremental backup).
O The ability to backup a file which won't fit on a
single disk.
O The ability to use both drives concurrently on a
system with two floppies.
O A slick intuition interface with pull-down menus and all that.
(any Modula-2 programmers out there want to vaulenteer for that?)
If you want any of these worked on first, or any of your own ideas,
please get in touch with me and let me know.
Also, a contribution of $10 would be greatly appreciated, and would assure
you of notification of future releases.
Chip Orange
The Backer, like The Restorer, ArchStatus and The Estimator, is freely
distributable for non-commercial purposes. It may be distributed with
commercial hard drives as long as no extra charge is made for it.
Version History:
1.7D -- Fixed illusive bug that would sometimes cause an error when creating
a directory on a floppy.
1.7C -- added more explicit error messages
1.7B -- recompiled with TDI version 3.02A, mysterious gurus gone!
1.7A -- Added buffering of listing file for more speed
1.7 -- Added ERRORS and LISTING parameters
1.6B -- Fixed minor bugs, now runs a little faster.
1.6 -- Added "best-fit algorithm" for file storage on floppies
1.5L -- Tinkered with the code so it uses a little less memory and runs a little faster
1.5K -- Properly detects and handles errors occuring during a format
1.5J -- Reduced stack size requirements
1.5I -- Thanks to the arp.library, parameter handling is now
a little better, and the prefix-string now defaults to todays date.
1.5F -- Removed some unnecessary code; runs a little faster now
1.5E -- allowed complete file names to be as long as 255 chars
1.5D -- minor bug fixes
1.5B -- first release