Szerszam Backup Utility

package main

Szbck wraps the system's rsync utility to create time machine like backups. It is driven by a backup configuration file which identifies the root directory to backup, a target directory to store snapshots, as well as enabling and disabling various rsync options, defines the default permissions for the root of each backup (snapshot) and lists items to exclude from backup and restores.

It can be used to backup a single machine and/or to keep several machines in sync. The utility defines several subcommands implementing the various backup functions as follows:

SubCommand  Description
==========  =============================================================
Help        Displays help on the utility and all of the subcommands.

Create      Creates a backup configuration file.

Snapshot    Creates a new backup snapshot hard linking unchanged items to
            previous snapshots.  It will implement a retention policy if
            and only if the --trim option is provided.

Restore     Restores/removes/replaces files in the source directory
            identified by the backup configuration file honoring all
            exclusions identified by the config file from a backup
            snapshot. The backup snapshot need not be from the same machine
            enabling syncing between machines.

Prune       Removes oldest backup snapshots.  NOTE: This does not
            implement a retention policy but simply purges the
            specified number of the oldest snapshots.  A retention
            policy has not yet been implemented.

Trim        Manually implements the retention policy as specified in the
            configuration file.  Can be invoked by using the --trim option
            on the snapshot subcommand.

Status        Reports on the number of backup snapshots and the space used
            overall and by each snapshot.

Vet         Parses a backup configuration file identifying any errors
            or problems without making any attempts at any operations.

Examples:

// Display help on the utility and all sub commands.
    szbck help

// Creates a new backup configuration file.
    szbck create -o config.szb -t backupTo /home/myDirectory

// Create a new snapshot.
    szbck snapshot config.szb

// Restore updated/missing files and purge extra files (unless the --keep
// option is specified).
    szbck restore config.szb

// Purge the oldest 5 snapshots from a backup set.
    szbck prune -n 5 config.szb

// Vet changes made to a config.szb file.
    szbck vet config.szb

Dedication

This project is dedicated to Reem. Your brilliance, courage, and quiet strength continue to inspire me. Every line is written in gratitude for the light and hope you brought into my life.

NOTE: Documentation reviewed and polished with the assistance of ChatGPT from OpenAI.