Help with number generation

[Jakkfrosted]

I'm using this bash script to generate 10 digit numbers:

head -c4 /dev/urandom| od -An -tu4

I have 2 issues to deal with.

1. This script often also generates 9 digit numbers.

2. I would like to generate all number sequences within a specific range without having to enter this script for one number at a time.

Also a question: If I can generate number sequences within a range will they all be unique (no repeats)?

Any help is appreciated.

Script source: Text Processing Commands

[nmset]

1.

r=$(head -n1 /dev/urandom | uuencode -m - | grep -o [0-9] | tail -n 10)
z=
for c in $r
do
z=$z$c
done
echo $z

Caveat : the number may start with zero !

2. Test for value z between desired range.

[nmset]

1.

This one is better, no leading zero :

r=0
while [ $r -lt 999999999 ]
do
  r=$(head -n1 /dev/urandom | uuencode -m - | tr -cd [0-9] | tail -c10)
done
echo $r

[nmset]

And this one sets the bounds :

r=0
lbound=2000000000
ubound=2300000000
while [ $r -lt $lbound ] || [ $r -gt $ubound ]
do
  r=$(head -n1 /dev/urandom | uuencode -m - | tr -cd [0-9] | tail -c10)
done
echo $r