HOWTO: Generate random numbers in command line

od -An -N2 -i /dev/random

`od` -- object dump tool
`-An` -- turns off address displaying
`-N2` -- number of bytes to extract
`-i` -- use integer as display format
`/dev/random` -- pure random bytes generator, built on time delay
between user input actions

touch `od -An -N2 -i /dev/random`.tmp

echo $(( 100+(`od -An -N2 -i /dev/random` )%(1000-100+1) ))

where `echo $((...))` is a simple calculation construct for bash, e.g.
`echo $((3+2))`

random number within range is given by
`min+( seed%(max - min + 1) )`

larger number of bytes can be obtained using `/dev/urandom` instead of
`/dev/random`