Internal Program Version:  S-Lang 2.2.4  (The HEADER-Files)

S-Lang is a multi-platform programmer's library designed to allow
a developer to create robust multi-platform software. It provides
facilities required by interactive applications such as display/screen
management, keyboard input, keymaps, and so on. The most exciting
feature of the library is the slang interpreter that may be easily
embedded into a program to make it extensible. While the emphasis
has always been on the embedded nature of the interpreter, it may
also be used in a stand-alone fashion through the use of slsh,
which is part of the S-Lang distribution.

http://www.s-lang.org/