D:\>perl -MPOSIX="log10,log2" -le "$r1=log(1234)/log(2);$r2=log10(1234)/log10(2);$r3=log2(1234)/log2(2);print $r1; print $r2; print $r3;"
10.269126679149417887862906163471
10.269126679149417887862906163471
10.269126679149417887862906163471