pre-change-snapshot

Pre-Change Snapshot

Create a "pre" snapshot to pair with a post-change snapshot for capturing deltas.

When to use

• Before running a complex operation (batch script, config migration, upgrade)
• Setting up a pre/post pair for change auditing
• Establishing a baseline before testing

Inputs to gather

• Snapper config name
• Description (what operation is about to run)

Procedure

1. Preflight: Verify snapper is installed and config exists.
2. Run sudo snapper -c <config> create --type pre --print-number -d "<description>".
3. Capture the numeric ID from stdout.
4. Print only the ID (e.g., 42) so the caller can capture it for later pairing.

Output / side effects

Pre snapshot created. Returns numeric snapshot ID for caller to reuse with --pre-number <id> in a post-change snapshot.

Safety / constraints

Creates a read-only snapshot. Minimal space overhead. Requires sudo. ID is intended to be captured by a wrapping workflow.