merge using wildcard on destination removes all of destination not just src files
#!perl -w
use strict;
my @includefiles = glob "*_includefile.txt";
foreach (@includefiles)
{
my $includefilename=$_;
if (m/(.*)(_includefile.txt)/) {
my $zipfilename = $1.".zip";
system("7za a -tzip -i@".$includefilename . " " .$zipfilename);
}
}