This is Version 9.4.3 of the Icon Program Library. For on-line documentation, see http://www.cs.arizona.edu/icon/v943/library/ipl.htm Unix users should generally not try to build the library separately, but instead should install Icon 9.4.3 as a whole, which includes the library. The MT-Icon portions of the library (the m*) directories are for use with specially configured versions of Icon, for which no support is provided.