Bash_Prog while loop and Delay

[1] http://www.faqs.org/docs/bashman/bashref_68.html




#!/bin/bash

var0=0
LIMIT=10

while [ ! -a /dev/ttyUSB3 ]

#while [ -a /dev/tty6 ]
do
echo "checking /dev/ttyUSB3 " # -n suppresses newline.
sleep 3
done

#exit 1