Not sure why you would want to start off with a big file but here you go, This makes a big file full of zeros. You could also use pack to get a null and fill it with those if you prefer. Or question marks as the requirement is puzzling :)

use strict; use warnings;

my $file = "test.meg";
my $mb   = 1024 * 1024;
my $meg  = '0' x $mb;

open my $fh, '>', $file or die "yuck, $file: $!\n";
print $fh $meg;
seek  $fh, 0, 0;  # rewind to print at start. I guess you want this
print $fh "I Write\n";
close $fh;

[download]

Cheers,
R.

Pereant, qui ante nos nostra dixerunt!

In reply to Re: how to give size to a file at the time of creation by Random_Walk
in thread how to give size to a file at the time of creation by Priti24

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