akorn’s gists

akorn / find-interface

Last active February 25, 2022 20:04

A script to be called from `pre-up` in `interfaces(5)`: it examines a set of configured candidate interfaces to find the one that's plugged into the network you want, then renames it to a descriptive name you've chosen. Use case: you have many similar physical interfaces and don't want to keep track of which cable you plug into which.

	#!/bin/zsh
	#
	# Copyright (c) 2019-2022 András Korn. License: GPLv3
	#
	# Take a set of network interfaces and determine which one is plugged into a specific network. Then rename the interface.
	#
	# This script supplies some generic functions for that purpose; the actual logic comes from configuration (you need to override the detect() function and perhaps the last_resort() function).
	#
	# The script is concurrency capable. It processes candidate interfaces simultaneously, obtaining a lock for each; other instances skip locked interfaces and add them to the end of their queue.
	# Several instances can run concurrently with overlapping candidate POOLs.

akorn / list-disk-status

Last active February 25, 2022 20:20

Query the status of all local SATA/SAS hard drives and summarize in a table; also for disks on hpsa controllers

	#!/bin/zsh
	#
	# Copyright (C) 2016, 2022 András Korn. Licensed under the GPL v3.
	#
	# Purpose: query the status of all local SATA hard drives and summarize in a table.
	#
	# Not complete, but good enough for my own purposes. Patches welcome.

	typeset -A diskattrs
	typeset -A diskargs

akorn / runcached

Last active September 3, 2024 22:15

Run specified (presumably expensive) command with specified arguments and cache result. If cache is fresh enough, don't run command again but return cached output.

	#!/bin/zsh
	#
	# Purpose: run specified command with specified arguments and cache result. If cache is fresh enough, don't run command again but return cached output.
	# Also cache exit status and stderr.
	# Copyright (c) 2019-2023 András Korn; License: GPLv3

	# Use silly long variable names to avoid clashing with whatever the invoked program might use
	RUNCACHED_MAX_AGE=${RUNCACHED_MAX_AGE:-300}
	RUNCACHED_IGNORE_ENV=${RUNCACHED_IGNORE_ENV:-0}
	RUNCACHED_IGNORE_PWD=${RUNCACHED_IGNORE_PWD:-0}

akorn / zfs-properties-backup.zsh

Created October 15, 2018 10:46

Script to back up zfs metadata, also in the form of zfs create commands

	#!/bin/zsh
	zfs get all -Hp -s local,received >/var/backups/zfs-properties.txt
	zpool get all >/var/backups/zpool-properties.txt
	for i in $(zfs list -t filesystem,volume -H -o name); do
	unset props
	zfs get all -o property,value -Hp -s local,received $i \| while read prop value; do
	props=($props[@] "-o $prop"="'$value'")
	done
	echo zfs create ${(o)props[@]} $i
	done >/var/backups/zfs-create-commands.txt

akorn / browser-suspender

Last active May 19, 2020 13:19

A zsh script to automatically suspend browser instances that don't have focus, and unsuspend them when they receive focus. They get to run for a bit every few minutes even if they don't have focus so they can update/display notifications etc.

	#!/bin/zsh
	#
	# Idea from http://log.or.cz/?p=356
	#
	# Copyright (c) 2017-2020 András Korn. License: GPLv3
	#
	# Run this from a user-level runsvdir (runit), or from an endless loop, or using systemd, set to restart.
	#
	# Make sure you start browsers in their own process group (e.g. `chpst -P browser`). (TODO: maybe support cgroups?)

akorn / rsync_parallel.sh

Last active September 13, 2024 17:04 — forked from rcoup/rsync_parallel.sh

This script can transfer large directory structures with parallel rsync workers. Example command line: `rsync_parallel . -- -aHSAX --exclude '*13' . /tmp/2/.`

	#!/bin/zsh
	#
	# Copyright (c) 2014, 2020 by Dr. András Korn. Implements the basic idea of a similar script by Robert Coup (2013).
	# License: GPLv3

	function usage() {
	echo 'Usage:

	rsync_parallel [--parallel=N] <args to find(1) to generate list of stuff to transfer> -- <args to rsync>

Dr. András Korn akorn