I would recommend reading the file in once. Then updating the array by inserting each new entry in it's proper place with splice. When finished inserting all the new entries, write the file out once.

my @reg_addrs = qw(bob@domain1.com bob@domain2.com);
open FH,"<",$datafile or die "Could not read virtual file";
my @virtual = <FH>;
close FH;
for my $reg_addr (@reg_addrs) {
    my ($name,$domain) = split /@/,$reg_addr;
    my ($i) = 0;
    for my $entry (@virtual) {
        ++$i;
        if ($entry =~ /\Q$domain\E/) {
            splice @virtual,$i,0,"$reg_addr\t$user\n";
            last;
        }
    }
}
open FH,">",$datafile or die "Could not write virtual file";
print FH @virtual;
close FH;

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dragonchild

In reply to Re: running same bit of code twice by pfaut
in thread running same bit of code twice by Anonymous Monk

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