Here's one way on a 64-bit capable build, provided your prng can produce at least 8-bit rands: 

sub rand64{ unpack 'Q', pack 'C8', map rand(256), 1 .. 8; }

for(1..10){ 
    my $rand64 = rand64(); 
    printf "%64s %16s %I64U\n", 
        unpack( 'b64', pack( 'Q', $rand64 ) ), 
        unpack( 'H16', pack( 'Q', $rand64 ) ), 
        $rand64; 
}

1010111111000000011010001011001101101010011001011110100101011101 f5031
+6cd56a697ba 13445398104276075509
1011010011110001101111011011100010001000001100000001011101111110 2d8fb
+d1d110ce87e 9144572311028731693
1100000000001011011000101111011110001110110110001110000000101001 03d04
+6ef711b0794 10666524418609958915
1000101001111110010101010010011101000111000011010101100000110110 517ea
+ae4e2b01a6c 7789732994036170321
0010010000011010010011110001100000111110001011000100110111110011 2458f
+2187c34b2cf 14966082219304704036
1111100110000001010110000110011011011100010010001001000100101101 9f811
+a663b1289b4 13008949044961771935
1001111000111111101110010111001111010011011111001110101110101100 79fc9
+dcecb3ed735 3879638649068715129
0000010011010010001110011101111101011111001001110101001011100101 204b9
+cfbfae44aa7 12054699119224834848
1110111000010100001101010110011111010011111011000100010111100011 7728a
+ce6cb37a2c7 14385121508662716535
0011110011100110111011000101100110100100100110101101011101011000 3c673
+79a2559eb1a 1939742082549114684

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In reply to Re: how to get a 64bit random number with rand() ? by BrowserUk
in thread how to get a 64bit random number with rand() ? by iglake

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