Hi I need to sort a file in.txt as shown below 

05,sometext5

02,sometext2

10,sometext10

03,sometext3

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and need the sorted one as below 

02,sometext2
03,sometext3
05,sometext5
10,sometext10

[download]
i used tell and seek function to swap this. But one of my main aim is performance ,because its going to handle a large files about 500 Mb to 1Gb I wrote the below code. It works fine but takes time for large files. Any suggestions please Regards, blackdragoen 
open(IN,"in.txt");
while(<IN>)
{
    if($_=~m/^\n/)
    {
            $tell_val=tell();
    }
        if($_=~m/^\d+/)
        {
        $has{$&}=$tell_val if($tell_val ne '');
        }
}
open(OUT,">output.txt");
foreach(sort{$a<=>$b}(keys %has))
{
        seek(IN,$has{$_},0);
        $line=<IN>;
        print OUT $line;
        print $_;
}

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In reply to Sort lines in a file by blackdragoen

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