The first argument to join is the string that will be inserted between the rest of the arguments.
That is join '', $d1, $d2, $d3, $d4; is "$d1$d2$d3$d4" but join $d1, $d2, $d3, $d4; is "$d2$d1$d3$d1$d4".

In reply to Re^5: Need a wait to generate a 4 digit "PIN" number by lidden
in thread Need a wait to generate a 4 digit "PIN" number by jaiello

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