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Korn Shell 93 Hash Builtins

This post shows you how to incorporate hash functions built into the AT&T Advanced Software Technologies (AST) libsum library in your Korn shell shell scripts via custom builtins in a dynamically loadable plugin.

GRUB2 Modules

This post describes GRUB2 modules and shows you how to add functionality to existing modules or write you own custom module.

Hard Disk Metadata

This post demonstrates how to access hard disk metadata such as disk geometry, capacility, manufacturer, serial number, firmware revision, rotational speed, and partiitioning information using libparted and various ioctls and output the metadata in a number of formats.


This post examines what support is provided by OpenSSL v1.0 for the Data Encryption Standard (DES) and provides simple examples of how to used the provided application programming interfaces. A brief overview of DES and the algorithmic implementation of DES known as Data Encryption Algorithm (DEA) is also provided.

KSH93 libshell

In a number of posts about a year ago I discussed how to develop custom builtins for Korn Shell 93 (ksh93) using libshell and published APIs. You can also use these same APIs to access ksh93 functionality from within a C application. This post provides three simple examples of how to do this.