Check if AWK supports substr() function. If successful execute ACTION-IF-SUCCESS otherwise ACTION-IF-FAILURE.
This work is heavily based upon testawk.sh script by Heiner Steven. You should find his script (and related works) at <http://www.shelldorado.com/articles/awkcompat.html>. Thanks to Alessandro Massignan for his suggestions and extensive nawk tests on FreeBSD.
Download the latest version of ax_check_awk_substr.m4 or browse the macro’s revision history.
Copyright © 2009 Francesco Salvestrini email@example.com
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