#!/usr/bin/env sh

# @(#) a1       Demonstrate one debugging feature in [g]awk.

set -o nounset
echo

## Use local command version for the commands in this demonstration.

echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version bash awk

echo

awk --lint '
b == 1  { print " Found case for value of b is 1." }
' data1

exit 0

% ./a1

(Versions displayed with local utility "version")
GNU bash 2.05b.0
GNU Awk 3.1.4

awk: cmd. line:2: (FILENAME=data1 FNR=1) warning: reference to uninitialized variable `b'
awk: cmd. line:2: (FILENAME=data1 FNR=2) warning: reference to uninitialized variable `b'
awk: cmd. line:2: (FILENAME=data1 FNR=3) warning: reference to uninitialized variable `b'