Ghostscript is a processor for PostScript and PDF files. It can rasterize these files to a wide variety of printers, devices for screen preview, and image file formats. Since applications tend to prepare pages for printing in a high-level format such as PostScript, most Unix users with low-level bitmap printers, such as inkjets, use GhostScript as part of the printing process. In addition, Ghostscript is capable of converting PostScript files, functionality comparable to Adobe Acrobat Distiller, but on the command line. In addition, Ghostscript is used for file import and viewing by a great many other applications, including xv, ImageMagick, gimp, and xdvi. Several GUI wrappers for viewing PostScript and PDF files exist, including GSview, ghostview, gv, ggv, and kghostview. This is far from a comprehensive list.
album is a free HTML/XHTML photo album and gallery generator that supports themes/skins. You can choose different themes or write your own to get different layouts and styles. It creates all your thumbnails (including directory thumbnails) and descends into directories so you can organize your photos. See the home page for more examples. album is also multi-lingual, with many languages being added all the time. N.B.: The purchase link is provided for donations; the software does not cost anything.
Ansiprint is a utility for printing text files (or stdin) from remote terminals using ANSI telnet escape sequences. It was inspired by the ansiprt.c component of the University of Washington's excellent email package, PINE. However, since the author believed that ansiprt.c was released under "somewhat ridiculous terms", ansiprint has been completely re-written in C++, and includes a variety of new features.
Calc is arbitrary precision arithmetic system that uses a C-like language. It's useful as a calculator, an algorithm prototype, and as a mathematical research tool. More importantly, calc provides a machine-independent means of computation. Calc comes with a rich set of builtin mathematical and programmatic functions.
CDSA stands for Common Data Security Architecture. It provides a security framework that includes cryptographically signed modules to present an abstracted unified API to the application developer to perform cryptographic and security related operations. It also includes hardware support for cryptographic tokens and biometric devices, such as thumbprint scanners. Intel has implemented the CDSA 2 specification and released it as open source.
cfv is a utility to both test and create .sfv (Simple File Verify), .csv, .crc, .md5(sfv style), md5sum, BSD md5, sha1sum, and .torrent checksum verification files. It also includes test-only support for .par and .par2 files. These files are commonly used to ensure the correct retrieval or storage of data.
cgi-util is a fast, easy to use C library for creating CGI programs. Functions are available for initialization (parsing), grabbing fields (by string, integer, double or boolean value), embedding HTML files, and more. It accepts both POST and GET request methods and has extensive error handling.