pure bash bash64.sh

pbash64.sh

#!/bin/bash
B=({A..Z} {a..z} {0..9});p=printf\ ;I=$(B=$@
for((;i<${#B};i++)){ for y in {31..128};{
[[ ${B:i:1} = "$($p\\x`$p%x $y`)" ]]&&(a()((q=y/2,r=y%2));a;o=$r
for((;q;)){ y=$q;a;o=$r$o;};$p%08d $o)} })
for((;e<${#I};e+=6)){ y=${I:e:6}0000;O+=${B[2#${y::6}]};}
for((;${#O}%4;)){ O+=\=;}
$p$O

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