René Hansen rhardih

rhardih / zip_file_names.rb

Last active April 25, 2021 23:21

Listing filenames of a remote ZIP archive without downloading entire file

	require 'httparty'
	require 'uri'

	def get_file_names(zip_url)
	# ZIP file format: https://en.wikipedia.org/wiki/ZIP_(file_format)

	# 1. Do an initial head request to figure out how big the file is from the
	# content size
	response = HTTParty.head(zip_url)

rhardih / out.sh

Created November 22, 2017 14:23

http-server vs. http.listenAndServe scale

	# http-server
	rene $ for i in 16 128; do ab -c $i -n $i http://127.0.0.1:8080/ \| grep "Time per"; done
	Time per request: 20.492 [ms] (mean)
	Time per request: 1.281 [ms] (mean, across all concurrent requests)
	Time per request: 138.750 [ms] (mean)
	Time per request: 1.084 [ms] (mean, across all concurrent requests)

	# serve
	rene $ for i in 16 128; do ab -c $i -n $i http://127.0.0.1:8080/ \| grep "Time per"; done
	Time per request: 3.465 [ms] (mean)

rhardih / call.sh

Last active October 25, 2017 11:32

valgrind callgrind Unrecognised instruction on macOS 10.12.6

valgrind --tool=callgrind ./oclinf

rhardih / Makefile

Created September 8, 2017 11:10

OpenCV cv::ocl::attachContext problem

	INC=-I/Users/rene/Code/OpenCL-Headers/opencl12
	PKG=`pkg-config --cflags --libs opencv`
	LD=`pkg-config --libs-only-L opencv \| cut -c 3-`

	.PHONY: default a.out.lldb
	default: build
	LD_LIBRARY_PATH=$(LD) ./a.out

	lldb: build a.out.lldb
	LD_LIBRARY_PATH=$(LD) lldb --source a.out.lldb

rhardih / out.sh

Created November 22, 2016 14:26

Leptonica build fails to find include of custom compiled version of libjpeg

	rene $ ls -la
	total 0
	drwxr-xr-x 2 rene staff 68 Nov 22 15:22 .
	drwxr-xr-x 26 rene staff 884 Nov 22 14:15 ..
	[~/Code/leptonica/build] (master)
	rene $ tree ../dependencies/install/
	../dependencies/install/
	├── bin
	│ ├── cjpeg
	│ ├── djpeg

rhardih / rf.sh

Created November 20, 2016 17:08

List a random file from the current directory

ls | head -$(($RANDOM % `ls | wc -l` + 1)) | tail -1

rhardih / md5c.sh

Created November 2, 2016 11:42

Bash utility shorthand to validate md5 checksums on files

	#!/usr/bin/env bash

	# md5c
	#
	# Perform md5 checksum validation of a file against
	# a specified md5 hash.
	#
	# usage: md5c filename hash
	function md5c {
	filename="$1"

rhardih / when.js

Created April 18, 2016 14:50

Simple handler class providing callbacks when dom objects scroll into view

	var WhenHandler = function(id) {
	this.elm = document.querySelector("#" + id);
	this.scrolled_into_view = false;
	this.scroll_callback;

	this.doc = document.documentElement;
	this.doc_bounds = this.doc.getBoundingClientRect();
	this.elm_bounds = this.elm.getBoundingClientRect();
	}

rhardih / pointer_fun.c

Created October 19, 2015 23:28

Simple example of manipulating contents of a pointer from within a function call.

	#include <stdio.h>
	#include <stdlib.h>

	int pointer_pointer_function(int **pp)
	{

	printf("EQUAL WAYS OF ADDRESSING:\n");
	printf("(pp + 0): %d\n", (int) (pp + 0));
	printf("(pp + 1): %d\n", (int) (pp + 1));
	printf("(pp + 2): %d\n", (int) (pp + 2));

rhardih / convert.sh

Created August 26, 2015 17:18

Recursively find and convert .epub to .mobi using calibres ebook-convert (in parallel)

find . -name "*.epub" -exec sh -c 'ebook-convert "{}" "$(dirname "{}")/$(basename -s .epub "{}").mobi" &' \;