Use an index for your array of fields, combined with the /g modifier. This one works:

#!/usr/bin/perl -w
use strict;
my $line =
    "00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,01,00,00,00,"
   ."02,00,01,00,39,00,39,00,39,00,39,00,30,00,30,00,30,00,30,00,"
   ."00,00,00,00,00,00,00,00,00,00,";

my @fields = (100, 101, 102, 103);

my $index =0;

$line =~ s/\b39\b/$fields[$index++]/g;

print $line;
__END__
output:
00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,01,00,00,\ 
00,02,00,01,00,100,00,101,00,102,00,103,00,30,00,30,00,30, \
00,30,00,00,00,00,00,00,00,00,00,00,00,
[download]

See perlre for an explanation of the modifiers I have used here.

It's not really clear what you are trying to do, but here are my assumptions:

I assume that the above line is an actual line from the file, and depending on how you have read it in, it most probably is getting read line by line, therefore, $line will not contain the concatenated lines together and that's why your regex is not working (besides escaping the \ of \r and \n)... so here's a quick snippet illustrating how to do it (using same regex from Re: Including special characters in a search and replace):

open IN, "<", "thefile.ext" or die "Cannot open file: $!\n";
my $i = 0;
while (my $line = <IN>) {
       $line =~ s/,39,/,3$fields[$i++],/g;

       # now what you want to do with $line is up to you
}
close IN;
[download]

I think you've got it pretty much covered Chady and Caron.

The lines are a section of hex from a Windows registry file & the 39's are the first four digits of a user's access code to use a specific color laser printer. I'm reading a code in based on username and trying to replace the four 9's with each user's specific code.

The fact that it's on multiple lines is definately part of my problem. I also was trying to escape my \n characters as well. I didn't realize I could each value without specifying the whole line. Here is my finished output:



#!/usr/bin/perl
open (USERS, "user.txt") or die "Cannot open file user.txt: $!\n";
@users = (<USERS>);
close USERS;

foreach (@users){
    chomp;
    ($userid,$acode) = split/\|/;
    if ($userid eq $ENV{"USERNAME"}) {
        @fields = split //, $acode;

        open(REG, "template.reg") or die "Cannot open file template.re
+g: $!\n";
        @hex =(<REG>);;
        close(REG);

        open(NEWREG, "> import.reg") or die "Cannot open file import.r
+eg: $!\n";
        foreach $line (@hex){
            my $i = 0;
            $line =~ s/,39,/,3$fields[$i++],/g;
            print NEWREG "$line";

        }
        close(NEWREG);
    }
}
[download]



Thanks for the assistance!

$line =~ s/39/3$fields[0]/;
$line =~ s/39/3$fields[1]/;
$line =~ s/39/3$fields[2]/;
$line =~ s/39/3$fields[3]/;
[download]

Update: This answer is getting voted down a lot. Maybe I am blind today, but could someone point out what is wrong with it?