A simple "oneliner" for a random 8 character password with strip out meta characters :
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head -c 4 /dev/random | uuencode -m - | tail -n 2 | head -n 1 | sed 's/[^a-Z0-9]/K/g'
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Another example:
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#!/bin/bash
MAXSIZE=62
array1=(
q w e r t y u i o p a s d f g h j k l z x c v b n m Q W E R T Y U I O P A S D
F G H J K L Z X C V B N M 1 2 3 4 5 6 7 8 9 0 \! \@ \# \$ \% \^ \& \* \( \)
\! \@ \# \$ \% \^ \& \* \( \) \! \@ \# \$ \% \^ \& \* \( \) \! \@ \# \$ \%
)
MODNUM=${#array1[*]}
pwd_len=0
while [ $pwd_len -lt $MAXSIZE ]
do
index=$(($RANDOM%$MODNUM))
echo -n "${array1[$index]}"
((pwd_len++))
done
echo
exit 0
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