How to add text to the beginning of a line?

Question

Perl

Please help
How can I add Privet to an existing tmp.txt file that has a line?
The code must be written in the Perl script itself, and not a call from the command line

Answer 1

open F, "+<", "tmp.txt";
$a = do { local $/; };
seek F, 0, 0;
print F "Privet\n", $a;
close F;