open $srcFile, '<', 'source.txt' or die $!
my $metaText = "";

while( my $line = <$srcFile> )
{
    if( $line =~ m/<text>(.*)<\/text>/ )
    {
        # Replace the old meta text with the new one.
        $metaText = $1;
    }
    else
    {
        # Normal line. The old meta text applies.
        
        my @words = split /\s+/ $line;
        
        foreach my $word (@words)
        {
            store_in_index($metaText, $word);
        }
    }
}

close $srcFile;