It is configured via a script created by the autoconfig utility and compiled using an ANSI-C compiler. As such it is portable to a wide range of platforms. The documentation is contained within, believe it or not, a Texinfo document and can thus be printed or viewed online. There are at least two programs currently available to translate Texinfo files in standard HTML and thus make them readable via standard hypertext browsers, making a third document format possibility. Binary versions are available in both a.out and ELF format, and the source code is available at your friendly local GNU mirror.
Rudimentary documentation is available in texinfo format.
An Xlib based 2-D drawing facility under X11 . Tgif can also be launched as an external viewer by Mosaic or Netscape by including the proper incantations in your MIME configuration files. The documentation is contained within a man page for which a PostScript version is available. I've installed it on my Linux box and find it most useful for varied tasks. A large set of advanced tools like a spell checker are built-in, and it can export documents to common formats like HTML and LaTeX .