Ian Davies daviesian

After changing IP in router config:

sudo dhclient -r && sudo dhclient

List audio devices:

aplay -l

or

aplay -L

Useful articles

SmartOS Documentation

Global config

To detect all silences longer than a second:

TIMES=`/c/dev/bin/ffmpeg-20160425-git-9ac154d-win64-static/bin/ffmpeg.exe -i ~/Desktop/DW33\ -\ Going\ Postal/Going\ Postal\ 01\ -\ Terry\ Pratchett.mp3 -af silencedetect=noise=0.001:d=1 -f null - 2>&1 | grep -E '^\[silence.*start' | cut --delimiter=\  --fields=5 | tr '\n' ','

To split file at those times:

/c/dev/bin/ffmpeg-20160425-git-9ac154d-win64-static/bin/ffmpeg.exe -i ~/Desktop/DW33\ -\ Going\ Postal/Going\ Postal\ 01\ -\ Terry\ Pratchett.mp3 -acodec copy -f segment -segment_times ${TIMES::-1} thing-%03d.mp3 2>&1

PostgreSQL Replication with Docker

Configuration

Make sure nothing exists already: docker-compose down -v
Create a blank DB in volume data-1, then start service pg1 using it: docker-compose run --rm pg1-create-primary && docker-compose up pg1
From another server, back up the data-1 db into data-2, then run pg2 as a hot-standby: docker-compose run --rm pg2-create-standby && docker-compose up pg2

	;; This is core.clj from a lein2 project with the dependency [com.datomic/datomic-free "0.8.3397"]
	;;
	;; Based on the tutorial at http://docs.datomic.com/tutorial.html

	(ns datomic-test.core
	(:use [datomic.api :only [q db] :as d]
	[clojure.pprint]))

	(ns datomic-test.numbers
	(:use [datomic.api :only [q db] :as d]
	[clojure.pprint]
	[datomic-test.datomic-helpers]))

	(def uri "datomic:mem://numbers")

	(d/create-database uri)

	(def conn (d/connect uri))

	(ns meta-ex-client.core
	(:use compojure.core
	compojure.route
	aleph.tcp
	gloss.core
	lamina.core
	clojure.data.json
	clojure.pprint))

	user=> Exception in thread "nREPL-worker-0" java.lang.NullPointerException
	at clojure.core$refer.doInvoke(core.clj:3779)
	at clojure.lang.RestFn.applyTo(RestFn.java:139)
	at clojure.core$apply.invoke(core.clj:603)
	at clojure.core$load_lib.doInvoke(core.clj:5279)
	at clojure.lang.RestFn.applyTo(RestFn.java:142)
	at clojure.core$apply.invoke(core.clj:603)
	at clojure.core$load_libs.doInvoke(core.clj:5298)
	at clojure.lang.RestFn.applyTo(RestFn.java:137)
	at clojure.core$apply.invoke(core.clj:605)

	;; Eval all this in the scratch buffer, then have a play with evaluating forms in a clojure buffer.
	;; This is a very quick and dirty first version.

	(setq thread-count 0)

	(defun add-remote-thread ()
	(setq thread-count (+ 1 thread-count))
	(setq mode-name (format "Clojure{%d}" thread-count))
	(force-mode-line-update))

	;; After connecting an nrepl client repl to an nrepl server, some
	;; output will still appear on stdout from the server.

	;; Try these snippets - they will both produce output on the nrepl server
	;; Java libraries commonly do both these things.

	(.println System/out "Hello stdout.")
	(.start (Thread. #(println "Hello from a new thread.")))

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