#!/bin/sh
F=/var/lib/cdebconf/templates.dat
N=$(grep -n 'Change mirror' "$F" | head -1 | cut -d: -f1)
echo "Change mirror 命中行 N=$N"
[ -n "$N" ] && sed -n "$((N-25)),$((N+2))p" "$F" | grep -iE '^(Name|Type|Default|Choices):'