Shell Programming and Scripting

cat random_password.ksh
#!/bin/ksh
mkrandpwd()
{
let MINIMUM_LEN=5
let MAXIMUM_LEN=20
#### 
#### Set the array of valid characters to be all upper and
#### lower case letters, all digits, and a selected set of
#### punctuation symbols.
#### 
　
set -A CHARS a b c d e f g h i j k l m n o p q r s t u v w x y z \
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z \
0 1 2 3 4 5 6 7 8 9 \; \: \. \~ \! \@ \# \$ \% \^ \& \* - + = \? 
　
CNUM="${#CHARS[@]}"

################################################################

#### Calculate a random length for the random password string between the
#### MINIMUM_LEN and MAXIMUM_LEN values provided
#### 
MAXLEN=$(( $MINIMUM_LEN + ( $RANDOM % ( $MAXIMUM_LEN - $MINIMUM_LEN ) ) ))

#### 
#### extract a random character from the CHARS array for each position
#### of the random password string. The length of the random string 
#### determined by the MAXLEN variable.
#### 
RANDSTR=""
let POSCNT=0; 
while [ 1 -eq 1 ] 
do
if [ $POSCNT -ge $MAXLEN ]
then
break;
fi
let POSCNT=$POSCNT+1
#### 
#### Using the modulo of a random number divided by the number of 
#### characters (array elements) in the CHARS array, provides a
#### random array element position. The random array element position
#### is used to append a single character at a time from the CHARS array
#### onto the random password string variable RANDSTR.
#### 
RANDSTR="${RANDSTR}${CHARS[${RANDOM}%${CNUM}]}"
done
　
echo "password=${RANDSTR} length=${MAXLEN}"
return 0
}
mkrandpwd

password=KBIJAuEBax0JciX           length=15
password=e+JUKKO9TJPCQ%.G     length=16
password=ZSJ5V7Qrl                    length=9
password=-;Kk+C2hE3z+hoLKH-    length=18

#!/bin/ksh
genstr()
{
    # generate a readom string contaning n characters from a supplied
    # list of chars
    #
    # usage: genstr <n> <listchar ...>
    #
    # eg:  genstr 8 0 1 would generate an 8 digit binary number
    #
    LEN=$1
    shift
    set -A CHARS $@
    CNUM="${#CHARS[@]}"
    RANDSTR=""
    let POSCNT=0;
    while true
    do
        [ $POSCNT -ge $LEN ] && break;
        let POSCNT=$POSCNT+1
        RANDSTR="${RANDSTR}${CHARS[${RANDOM}%${CNUM}]}"
    done
    echo "${RANDSTR}"
}
need=$(genstr 1 1 2 3 4)
genstr $need 0 1

100
00
0001
000
10
1100
1
1010
111
10

use strict;
use warnings;

$\ = "\n";
$, = '';

if (@ARGV < 3) {
    use File::Basename;
    my $NAME = basename $0;

    print STDERR "USAGE: $NAME <count> <length> <word>...";
    print STDERR '    <count> and <length> are <n> or <min>-<max>';
    exit 1;
}

my $count  = shift @ARGV;

my ($count_n, $count_w) = $count =~ m{^(\d+)(?:-(\d+))?} ;

if (defined $count_w) {
    if ($count_n < $count_w) {
        $count_w -= $count_n - 1;
    }
    else {
        print $ARGV, '(', $., '): invalid count - ', $count;
        next;
    }
}
elsif (defined $count_n) {
    $count_w = 1;
}
else {
    print $ARGV, '(', $., '): invalid count - ', $count;
    next;
}

my $length = shift @ARGV;

my ($length_n, $length_w) = $length =~ m{^(\d+)(?:-(\d+))?} ;

if (defined $length_w) {
    if ($length_n < $length_w) {
        $length_w -= $length_n - 1;
    }
    else {
        print $ARGV, '(', $., '): invalid length - ', $length;
        next;
    }
}
elsif (defined $length_n) {
    $length_w = 1;
}
else {
    print $ARGV, '(', $., '): invalid length - ', $length;
    next;
}

my $c = $count_n + int rand $count_w;

while (0 < $c--) {
    my @R = ();

    my $l = $length_n + int rand $length_w;

    while (0 < $l--) {
        push @R, $ARGV[int rand @ARGV];
    }

    print @R;
}

scriptname count length word...

./scriptname 10 1-4 0 1

01
1
01
1
101
010
10
001
1
01

./scriptname  1-80 10-50 0 1
0010010110110111111001101011110110
1110010101110111000101110
00001100111000100101000101100100110000110
1010111011110100001100
0110100100010
001010001101000
00001011000011100110101001110101011011010001010
01000001110101111001101011000001101001101000
100100111111110011111010101101111101111001100111
11101000010
11111110001010011101000001011111101000101110
1100000101101001010
01001111010110111101111110000101
11111101111010010100010101101000101110011011
100011100000010101110100
1000111100101000111011011101101000

./scriptname  1-16 8-32 C T G A
CTGCCGAAAGCGGCTGGGTT
GAATCCCGC
AGACCACAAGAAAAGCCCTGC
GACAATCAATGATGCATCTCTGTCAGCTAA
TATGAGTTGTCCCGGCCGTT