Extension API Variables (The GNU Awk User’s Guide)

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17.4.13 API Variables

The API provides two sets of variables. The first provides information about the version of the API (both with which the extension was compiled, and with which gawk was compiled). The second provides information about how gawk was invoked.

Extension Versioning    API Version information.
Extension GMP/MPFR Versioning    Version information about GMP and MPFR.
Extension API Informational Variables    Variables providing information about gawk’s invocation.