Gabriel Falcão gabrielfalcao

>>> from signal import Signals
>>> possible_signals = [(name, getattr(signal, name)) for name in dir(Signals) if name == name.upper()]
>>> valid_signals = [(name, signal) for name, signal in possible_signals if isinstance(signal, Signals)]
>>> len(valid_signals)
41
>>> [(name, signal.real) for name, signal in valid_signals]
[('SIGABRT', 6),

I recently happened upon an implementation of popen() (different API, same idea) using clone(2), and so I opened an issue requesting use of vfork(2) or posix_spawn() for portability. It turns out that on Linux there's an important advantage to using clone(2). I think I should capture the things I wrote there in a better place. A gist, a blog, whatever.

So here goes.

Long ago, I, like many Unix fans, thought that fork(2) and the fork-exec process spawning model were the greatest thing, and the Windows sucked for only having [exec*()](http://pubs.opengroup.org/onlinepubs/9699919

	# Output a single frame from the video into an image file:
	ffmpeg -i input.mov -ss 00:00:14.435 -vframes 1 out.png

	# Output one image every second, named out1.png, out2.png, out3.png, etc.
	# The %01d dictates that the ordinal number of each output image will be formatted using 1 digits.
	ffmpeg -i input.mov -vf fps=1 out%d.png

	# Output one image every minute, named out001.jpg, out002.jpg, out003.jpg, etc.
	# The %02d dictates that the ordinal number of each output image will be formatted using 2 digits.
	ffmpeg -i input.mov -vf fps=1/60 out%02d.jpg

	#!/bin/bash

	original="$1"
	replacement="$2"

	echo "Replacing $original with $replacement"
	ack -l $original * \| cut -d: -f1 \| uniq \| xargs gsed -i "s,$original,$replacement,g"

	if [ -z $3 ]; then
	original=`echo $original \| tr '[:lower:]' '[:upper:]'`

	// Example of test pyramid using jest

	// Basic usage:
	// jest --selectProjects 'unit tests'
	// Assumes that you organize tests under __${type}_tests__/*/.js
	//

	const path = require('path');

	const correctPath = value => path.resolve(__dirname, value \|\| '');

	#!/usr/bin/env bash

	set -exu