May 26, 2018

General purpose, formatter-independent index processor

The program makeindex is a general purpose hierarchical index generator; it accepts one or more input files often produced by a text formatter such as TeX or troff, sorts the entries, and produces an output file which can be formatted. The index can have up to three levels 0, 1, and 2 of subitem nesting. The way in which words are flagged for indexing within the main document is specific to the formatter used; makeindex does not automate the process of selecting these words. As the output index is hierarchical, makeindex can be considered complementary to the awk1-based make.index1L system of Bentley and Kernighan, which is specific to troff1, generates non-hierarchical indices, and employs a much simpler syntax for indicating index entries.