Backup -- Directory File Backup

Syntax      Backup [option...] -from 'directory' -to 'directory'

Description Files in a source ("from") directory are copied to a destination
            ("to") directory based on the modification date.  By default, only
            files that already exist in both the source and destination
            directories are candidates for copying.  (The -a option can
            override this default.)  Backup does not actually make the copies.
            Instead, it generates a script of APW Shell Duplicate commands.
            (The -doit option can override this default.)

            Backup-s default operation is based on the premise that you already
            have an existing directory on two sets of disks (generally a hard
            disk and a set of 3.5-inch disks) and that you want to make sure
            that the files on one of the disks are the same as the files on the
            other disk.  Thus, it is the files on the destination ("to") disk
            that determine which files can be copied from the source ("from")
            disk.

            A shell Duplicate command is generated to the standard output file
            if
            o   a file on a source disk also exists on the destination disk,
                and
            o   the modification date of the source is newer than that of the
                destination.

            In addition to the basic function of generating shell duplicate
            commands, Backup also provides these services:

            o   Directories can be recursively processed, allowing processing
                of all directories and subdirectories contained with
                directories (-f).
            o   (More to come in the future, hopefully...)

Input       None.

Output      For each file to be copied, a shell Duplicate command is generated
            to the standard output file as follows:

            Duplicate FromFile ToFile

            If you are using the -e option, then the shell's Eject commands are
            generated at the end of the list of Duplicates.  These commands
            cause the source and/or destination disks to eject if the -from and
            -to options specify as parameters either or boths disks as
            removeable media (i.e. contained in a floppy disk drive).

Diagnostics Errors and warnings are written to the diagnostic output file.  If
            you specify the -p option, progress information is written to
            diagnostic output also.

Status      Backup may return the following status codes:

            0   No errors; Duplicate commands have been generated
            1   Parameter or option error
            2   System error
            3   No errors and no files to duplicate

            Note:  Backup returns a status code of 3 when no files need
            copying.  If no files are copied because NONE of the files in the
            source directory exists in the destination directory, Backup also
            reports a warning ot the diagnostic output file.  If there are no
            name matches, it is possible that your from/to pathnames were
            specified incorrectly.  Hence, Backup lets you know of the possible
            error.  Backup does not report this as an error if you use the -a
            option.

Options     -a  Normally, a file in the source ("from") is ignored if it does
                not exist in the destination ("to").  Using the -a option
                forces Backup to generate a shell Duplicate command for all
                files in the source that don't exist in the destination.

            -c  Create directories.  When a directory name doesn't exist in the
                destination disk and there are files in the source to copy, -c
                generates a shell Create command to create the directory on the
                destination disk.  Note that this option makes sense only if
                you are using the -a option.

            -doit
                When this option is specified, Backup will send a command
                string to the APW shell for direct execution instead of writing
                the command string to standard output.

            -e  Eject the disk(s) from the drive if the disk is removeable.
                Disks are ejected when Backup terminates if there are no files
                to duplicate.  If Duplicate commands are generated, then shell
                Eject commands are generated to eject the specified disk(s).

            -from directory
                Specify the directory from which to get the source list of
                files.  If this option is omitted, the list will be built from
                the current directory.  This directory may be specified as
                either a GS/OS pathname or device name.

            -lastcmd 'cmd'
                Generate the specified command as the last command.  For
                example, a Beep command could be generated to signal that all
                the duplicates have been completed.

            -p  Write Backup's version number and progress information to
                diagnostic output.

            -r  Recursively process subdirectories encountered.

            -t 'type'
                Consider only files of the specified 'type' as candidates for
                backup.  'type' may be specified as a decimal or hexadecimal
                (preceeded by '$') number, or as a 3 character mnemonic.
                Backup recognizes the following mnemonics:

                TXT - text files
                BIN - binary files
                SRC - APW source files
                OBJ - APW object files
                LIB - APW library files
                S16 - GS/OS applications
                RTL - Run Time Library files
                EXE - APW shell utilities
                PIF - Permanent initialization files
                TIF - Temporary initialization files
                NDA - New desk accessory files
                CDA - Classic desk accessory files
                TOL - Apple IIGS Tool files
                SYS - ProDOS 8 applications

            -to 'directory'
                Specify the directory from which to get the destination list of
                files.  If the -to option is omitted and the -from option was
                specified, the destination will default to the current
                directory.  You MUST specify the -to if -from is omitted.

Examples
            Backup -from .AppleDisk3.5A -to */APW -r

            Recursively compares files and directories on your first 3.5" drive
            to the corresponding files and directories in the APW directory of
            your boot drive.  This is a very easy way to update your APW system
            when an update is received.
