Finding Extensions (The GNU Awk User’s Guide)

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17.5 How gawk Finds Extensions

Compiled extensions have to be installed in a directory where gawk can find them. If gawk is configured and built in the default fashion, the directory in which to find extensions is /usr/local/lib/gawk. You can also specify a search path with a list of directories to search for compiled extensions. See section The AWKLIBPATH Environment Variable for more information.