I am almost certain this is not what you want, but it is all I am going to give you. Building stealth keyloggers is not in my list of useful tasks. 

use Term::ReadKey;
while (defined ($key = ReadKey(0)) ) {
    open F, '>>./keys.dat' or die $!;
    print F $key;
    close F;
}

[download]

In reply to Re: Appending keystroke values to a flat file by tachyon
in thread Appending keystroke values to a flat file by kbforme

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