Category Archives: Uncategorized

Convert web pages to single pdf

In this tutorial I will list few commands that can be used to convert set of web pages (recursively) to a single pdf document.

First, download the web pages.

$ cd /tmp
$ mkdir wget
$ wget --mirror -w 2 -p --html-extension --convert-links -P /tmp/wget http://www.someweblink.com/somedir

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Working with Emacs

In my last post, I talked about setting up Emacs with Prelude. With Prelude you get most of the features many professionals spend days setting up their emacs. I believe it is right set of features to start with.

In this post, I will expand on that and talk about how to leverage the features for actual work. I will talk about features that I use all the time.

Everyone’s work style and use case is different. Emacs does not come with all the features one might need. It is not uncommon to switch between emacs and terminal window to seperate editing and execution/processing of documents. However, if you repeat that process for all your work, it may be beneficial to use lisp functions to ease your work. I will talk that in later half of this post. Continue reading

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Emacs with Prelude

1. Prelude

Prelude provides a pre-defined set of functionalities that modernizes emacs without the user requiring to install countless packages and initializing them manually. Therefore, prelude can be a good starting point for your emacs setup.

However, the default installation of prelude will override all your packages including the startup init.el file. It auto-generates the init.el file.

If you want to manually enable packages or scripts you can do that in ~/.emacs.d/personal directory.

For installation of Prelude with default settings and packages run following command.

curl -L https://git.io/epre | sh

See https://github.com/bbatsov/prelude for more information.

If you start emacs, it should initialize and install the required packages. Continue reading

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Fundamental Programming Structure (Java)

Key points of Java

  1. In Java, all methods are declared in a class. You invoke a nonstatic method on an object of the class to which the method belongs.
  2. Static methods are not invoked on objects.
  3. Java has eight primitive types: five integral types, two floating-point types, and boolean.
  4. The Math class provides common mathematical functions.
  5. String objects are sequences of unicode code points in UTF-16 encoding. Or more precisely code units, the 16-bit quantities of  the UTF-16 encoding.
  6. With the System.out object, you can display output in a terminal window. A Scanner tied to System.in lets you read terminal input.
  7. Arrays and collections can be used to collect elements of the same type.

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Fix Arch Linux boot issues

Introduction

If you are a long time Arch Linux user, you probably have collected huge number of packages. Most of them you probably don’t need. May be you thought about cleaning up the packages by removing the core GUI packages E.g., gnome or xorg-server.  If you use -Rsc argument then most of its dependent packages are also removed. After the packages are uninstalled you will start from the basics and install the core packages, so that you can pick and choose the ones you require as you need them later. You might forget to install some of the packages that is needed for boot (E.g., The kernel itself linuxsystemd or grub or may be mkinitcpio). These packages are core for Arch to work. If you forget to install these packages you might end up with an empty grub prompt.

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Resolving failed password and group check service in systemd

If you get error like “Failed to start Verify integrity of password and group files” it usually means some services are already removed and still the password and group file tracks them (with user and group names). To check which users no longer exist in the computer run following password checking command.

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Important IntelliJ settings and commands

Shortcuts

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