Shell Programming and Scripting

awk 'BEGIN{FS=";"}NR==FNR{a[$1]=$2;next}a[$1]<$2||!a[$1]' template source

McAfee AntiSpyware Enterprise Module;8.7.0.129
Windows XP Service Pack 3;20080414.175805
McAfee VirusScan Enterprise
Altiris Version: 6.9.430.0

McAfee AntiSpyware Enterprise Module;8.7.0.130
MySQL ODBC 3.51 Driver;03.51.05 - Gamma

 awk -F"." 'NR==FNR{a[$1]++;next} !a[$1]' source template.txt

awk -F";" 'NR==FNR{a[$1]=$2;next} !a[$1] ||a[$1] < $2 ' source template.txt

#!/bin/sh
awk -F";" 'NR==FNR{a[$1]=$2;next} !a[$1] ||a[$1] < $2 ' source template.txt

BEGIN{FS=";"} NR==FNR{a[$1]=$2;next} !a[$1] ||a[$1] < $2

awk -f test.awk source template.txt