VMS style versioning backup of individual files

backupf.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+# vms_cp.sh — copy file with VMS-style version suffix (:1, :2, ...)
+# Usage: ./vms_cp.sh <filename>
+
+set -e
+
+if [ $# -ne 1 ]; then
+    echo "Usage: $0 <filename>"
+    exit 1
+fi
+
+src="$1"
+if [ ! -f "$src" ]; then
+    echo "Error: '$src' not found or not a regular file."
+    exit 1
+fi
+
+dir=$(dirname "$src")
+base=$(basename "$src")
+
+# Escape regex special chars for grep
+base_escaped=$(printf '%s\n' "$base" | sed 's/[][\.*^$(){}?+|/]/\\&/g')
+
+# Collect existing version numbers (files like name:1, name:2, etc.)
+versions=()
+while IFS= read -r f; do
+    [[ $f =~ :([0-9]+)$ ]] && versions+=("${BASH_REMATCH[1]}")
+done < <(ls "$dir" 2>/dev/null | grep -E "^${base_escaped}:[0-9]+$" || true)
+
+# Determine next version number
+if [ ${#versions[@]} -eq 0 ]; then
+    next_ver=1
+else
+    max_ver=$(printf "%s\n" "${versions[@]}" | sort -n | tail -1)
+    next_ver=$((max_ver + 1))
+fi
+
+dest="${src}:${next_ver}"
+cp -p -- "$src" "$dest"
+
+echo "Created backup: $dest"
+