Changes between S5R4 and POSIX `awk'
====================================

   The POSIX Command Language and Utilities standard for `awk'
introduced the following changes into the language:

   * The use of `-W' for implementation-specific options.

   * The use of `CONVFMT' for controlling the conversion of numbers to
     strings (see Conversion of Strings and Numbers: Conversion.).

   * The concept of a numeric string, and tighter comparison rules to go
     with it (see Comparison Expressions: Comparison Ops.).

   * More complete documentation of many of the previously undocumented
     features of the language.