You need to quotemeta since you are trying to match a list of fixed strings not a list of regular expressions. This also makes it easy to figure out the maximum length of "carry over" you need between buffers. 

#!/usr/bin/perl -w
use strict;

my @checklist;
my @testfile;
my $rulenames;
open( FILE, "wordlist" )
    or  die "Can't read wordlist: $!\n";
my $maxLen = 0;
while(  <FILE>  ) {
    next   if $_ =~ /^ *$/  ||  $_ =~ /^#/;
    $maxLen = length($_)   if  $maxLen < length($_);
    push @checklist, $_;
}
chomp @checklist;
close(FILE);
my $bufSize= 8*1024;
$bufSize= 2*$maxLen   if  $bufSize < 2*$maxLen;

my $GrepList = join '|', map quotemeta $_, @checklist;
$GrepList = qr/($GrepList)/i;

@ARGV = grep -f $_, <*>;
$/= \$bufSize;    # Have <> read $bufSize bytes
if(  @ARGV  ) {
    my $prev= "";
    while(  <>  ) {
        $_ =~ s/\n//g;
        if(  ($prev.$_) =~ /$GrepList/  ) {
            print "$ARGV : $1\n";
            close( ARGV );
            $prev= "";
        } elsif(  eof  ) {
            $prev= "";
        } else {
            $prev = substr( $_, -$maxLen );
        }
    }
}

[download]
Tested and works. Note that this assumes that you don't have huge runs of newlines in the middles of your matches.

                - tye

Updated: I originally left out the setting of $/.

In reply to Re: Shell Script Woes (tye's try) by tye
in thread Shell Script Woes by Limbic~Region

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