I'd use Text::CSV_XS to read the CSV file. I'd read the file you're trying to change a little at a time, looking for the delimiter, and insert the CSV records when I find it. 

my $record_end = qq{\$\$\$\$\n};
while (<DATAFILE>) {
    next if ( $_ ne $record_end );
    # insert stuff from CSV here
}
continue {
    print OUT;
}

[download]

You don't have to read all of any file at once or even mess around with regular expressions.

In reply to Re: Appending data to large files by kyle
in thread Appending data to large files by joec_

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