#!/bin/csh

# Syntax: Create_Key_Prime  -d num_digits   file
#
#  num_digits   how many decimal digits do you want me to use in constructing
#                     a Blum prime.
#  file         contains a guess at a prime number.  The guess needn't contain
#                     num_digits.  However, if it does, and if it is a Blum
#                     prime, then the guess is returned as the key_prime.
#  stdout       will be written with an approved Blum prime of num_digits

if ($#argv != 3) then
   echo "Usage: " $0 "  -d no_of_digits   guessfile"
   exit 1
endif

if( "$1" == "-d" ) then
   @ num_digits = $2
   shift ; shift
else
   echo "Usage: " $0 "  -d no_of_digits   guessfile
   echo "   .... Please specify the number of digits to be generated"
   echo "   .... by using the -d option"
   exit 1
endif

if ( ! -e $1 ) then
   echo "Cant find file " $1
   exit 1
endif



# cook up a name for a temporary workfile
set tf = ./keycreat_ugh.$$

# first, grab the bc program that does the Blum, Blum, and Shub generator
cp ./find_blum_prime_bc $tf
chmod 777 $tf

# grab the guess from guessfile
echo ' a = \' >> $tf
cat $1 >> $tf

# the number of digits to be generated was specified on the command line
echo ' l = \' >> $tf
echo $num_digits >> $tf

# tell bc to run the BBS generator
echo "k(a,l)" >> $tf

# fire up bc.  Output is directed to stdout as desired.
bc < $tf

# clean up the excess
rm $tf