Greg Donald : Author, software maker, RC airplane enthusiast, player of strung instruments, bibliophile.

Convert one m4a file to many mp3s

#!/bin/bash while [ $# -gt 0 ]; do ffmpeg -i "$1" 2> tmp.txt while read -r first _ _ start _ end; do if [[ $first = Chapter ]]; then read # discard line with Metadata: read _ _ chapter ffmpeg -vsync 2 -i "$1" -ss "${start%?}" -to "$end" -vn -ar 44100 -ac 2 -ab 128 -f mp3 "$chapter.mp3" </dev/null fi done <tmp.txt rm tmp.txt shift done

Read More...

mp3s (1)

How-to guide for beginner-level Linux Kernel patch submissions

Every day I see new Linux Kernel hackers fail at their first patch submission. I'm not an expert, but I've learned how the process works and most importantly I've learned how to avoid irritating Linux Kernel maintainers. The "maintainers" are the gate keepers to the Linux Kernel. If you piss them off you will never land any patches into the Linux Kernel. All Linux Kernel development takes place in the open and hundreds (thousands?) of Linux Kernel developers will see and possibly read your patch submissions. You will want to make every effort to submit the best possible patch you can. That's where I come in. If you follow my guide there's a better than average chance you will actually land your patch into the Linux Kernel. For a beginner I recommend working on the drivers/staging tree maintained by Greg Kroah-Hartman. Clone Greg KH's staging tree: > git clone git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git This will take a while. After that you need to checkou

Read More...

linux (9) kernel (5) git (3) sed (1) diff (1) patch (1)

Raspberry Pi LEDs Test

#!/usr/bin/env python3 import time import RPi.GPIO as GPIO GPIO.setmode( GPIO.BCM ) ENABLE = 1; DISABLE = 0 RED = 23; GREEN = 24; BLUE = 25 RGB = [ RED, GREEN, BLUE ] RGB2 = RGB[::-1]

Read More...

raspberry-pi (2)

Shell script to automate go lang pkg test coverage

#!/bin/sh PACKAGE=mypkg # set mode go test -coverprofile=coverage.out $PACKAGE go tool cover -func=coverage.out go tool cover -html=coverage.out # count mode go test -covermode=count -coverprofile=count.out $PACKAGE go tool cover -func=count.out go tool cover -html=count.out # more info: http://blog.golang.org/cover

Read More...

go-lang (3) testing (2)

go log function

func log(s ...interface{}) { f, err := os.OpenFile("info.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666) if err != nil { fmt.Printf("error opening log file: %v", err) os.Exit(1) } defer f.Close() log.SetOutput(f) ss := "" for _, p := range s { switch p.(type) { case bool: ss += fmt.Sprintf("%t ", p.(bool)) case int: ss += fmt.Sprintf("%d ", p.(int)) case float64: ss += fmt.Sprintf("%.2f ", p.(float64)) case string: ss += fmt.Sprintf("%s ", p.(string)) } } log.Println(ss) }

Read More...

go-lang (3)