hi, im trying to read a file line by line, and write it out to another file, but alternating each write such that it writes the line to the start of the file one time and to the end of the file the next. the code i have (below) gives me an output file where it seems that each time i move the filepointer to the start of the file and write, i'm overwriting the last thing i wrote at the start of the file. i am trying to have it so that each time i seek to the beginning, it seeks to the beginning and writes what i want before whatever is there (while preserving the existing data instead of overwriting it). here is the code i have: 
open (FIN, "<$ARGV[0]") || die "Input file: $!\n";
open (FOUT, ">$ARGV[0]-randomized") || die "Output file: $!\n";
$flag = 1;

#set autoflush on output filehandle
$oldfh = select(FOUT);
$| = 1;
select ($oldfh);

while (<FIN>) {
    if ($flag) {
        seek (FOUT, 0, 0) || die "Seek to beginning: $!\n";
        $flag = 0;
    } else {
        seek (FOUT, 0, 2) || die "Seek to end: $!\n";
        $flag = 1;
    }

    print FOUT $_;
}

close (FOUT);
close (FIN);

[download]
any suggestions on how to actually accomplish what i'm going for would be greatly appreciated. :-)

In reply to rearrange lines in file by ZxCv

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