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@mrmichalis
mrmichalis / centos_python_env_setup
Created October 20, 2015 16:10 — forked from floer32/centos_python_env_setup
CentOS 6: Install Python 2.7.4, pip, virtualenv, and virtualenvwrapper on CentOS (plus some bonus items at the end if you want). You should probably run with `sudo`.
#!/bin/bash
# Source: http://toomuchdata.com/2012/06/25/how-to-install-python-2-7-3-on-centos-6-2/
# Install stuff #
#################
# Install development tools and some misc. necessary packages
yum -y groupinstall "Development tools"
yum -y install zlib-devel # gen'l reqs
# source this code in a Bash shell ($ . django-csrftoken-login-demo.bash),
# and run with a DB name as parameter (e.g. $ django-csrftoken-login-demo demo)
django-csrftoken-login-demo() {
# -- CHANGE THESE VALUES TO MATCH YOUR ACCOUNT --
local HOSTING_USERID=9988
local HOSTING_PANEL_USER='customer@email.address'
local HOSTING_PANEL_PASS='my secret login password'
local HOSTING_DB_PREFIX='username_'
local DB_NAME=$HOSTING_DB_PREFIX$1
@mrmichalis
mrmichalis / main.py
Last active November 21, 2017 20:53 — forked from gear11/main.py
"""
A simple proxy server. Usage:
http://hostname:port/p/(URL to be proxied, minus protocol)
For example:
http://localhost:8080/p/www.google.com
"""

How does ls work?

I wanted to be really able to explain to a fair amount of detail how does the program ls actually work right from the moment you type the command name and hit ENTER. What goes on in user space and and in kernel space? This is my attempt and what I have learned so far on Linux (Fedora 19, 3.x kernel).

How does the shell find the location of 'ls' ?

import os
import pprint
import fnmatch
import time
import subprocess
def find_services_needing_restart():
services = {}
pids = [ f for f in os.listdir('/proc') if f.isdigit() and os.path.isdir(os.path.join('/proc', f)) ]

Let's say you have a Bash shell script, and you need to run a series of operations on another system (such as via ssh). There are a couple of ways to do this.

First, you can stage a child script on the remote system, then call it, passing along appropriate parameters. The problem with this is you will need to manually keep the remote script updated whenever you change it -- could be a bit of a challenge when you have something to execute on a number of remote servers (i.e., you have a backup script running on a central host, and it needs to put remote databases in hot backup mode before backing them up).

Another option is to embed the commands you want to run remotely within the ssh command line. But then you run into issues with escaping special characters, quoting, etc. This is ok if you only have a couple commands to run, but if it is a complex piece of Bash code, it can get a bit unwieldy.

So, to solve this, you can use a technique called rpcsh -- rpc in shell script, as follows:

First, place th

@mrmichalis
mrmichalis / javascript_resources.md
Created January 30, 2014 20:47 — forked from jookyboi/javascript_resources.md
Here are a set of libraries, plugins and guides which may be useful to your Javascript coding.

Libraries

  • jQuery - The de-facto library for the modern age. It makes things like HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a multitude of browsers.
  • Backbone - Backbone.js gives structure to web applications by providing models with key-value binding and custom events, collections with a rich API of enumerable functions, views with declarative event handling, and connects it all to your existing API over a RESTful JSON interface.
  • AngularJS - Conventions based MVC framework for HTML5 apps.
  • Underscore - Underscore is a utility-belt library for JavaScript that provides a lot of the functional programming support that you would expect in Prototype.js (or Ruby), but without extending any of the built-in JavaScript objects.
  • lawnchair - Key/value store adapter for indexdb, localStorage
@mrmichalis
mrmichalis / python_resources.md
Created January 30, 2014 20:47 — forked from jookyboi/python_resources.md
Python-related modules and guides.

Packages

  • lxml - Pythonic binding for the C libraries libxml2 and libxslt.
  • boto - Python interface to Amazon Web Services
  • Django - Django is a high-level Python Web framework that encourages rapid development and clean, pragmatic design.
  • Fabric - Library and command-line tool for streamlining the use of SSH for application deployment or systems administration task.
  • PyMongo - Tools for working with MongoDB, and is the recommended way to work with MongoDB from Python.
  • Celery - Task queue to distribute work across threads or machines.
  • pytz - pytz brings the Olson tz database into Python. This library allows accurate and cross platform timezone calculations using Python 2.4 or higher.

Guides

@mrmichalis
mrmichalis / 0_reuse_code.js
Created January 30, 2014 20:46
Here are some things you can do with Gists in GistBox.
// Use Gists to store code you would like to remember later on
console.log(window); // log the "window" object to the console
#!/bin/bash
MSG=`sudo apt-get --yes dist-upgrade`
MSG_HEADING='sudo apt-get --yes dist-upgrade'
GmailSend.py -u bla@gmail.com -p bla -t bla@gmail.com -s "server update" -b "$MSG_HEADING \n\n $MSG"