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joec@home

Feb 8 2009, 03:46 AM

I am playing around on a Linux workstation using bash, sh and galeon just for fun to program fun scripts and games similar to use BASIC back in the old DOS days. Input is from terminal, scripts are run in sh and the output goes to the galeon web browser. (Sorry, I did not find the commands I really wanted to use Firefox!) Slowly I am remembering subroutines I used to use in basic and porting them over to sh and bash. While I am using galeon I am certain with some tweaking these can prove to be of value in other applications so I will be posting some of them here.

CODE

#/bin/sh
### Standard Functions

htm_out(){
###############################################
### Output to galeon web browser
###############################################
# $description5 Reserved for error codes
###############################################
 echo '<html><center><h3>'$tite'</h3></center>' > 6_out.htm
 echo ' '$description1'' >> 6_out.htm
 echo ' '$description2'' >> 6_out.htm
 echo ' '$description3'' >> 6_out.htm
 echo ' '$description4'' >> 6_out.htm
 echo ' '$description5'' >> 6_out.htm
 galeon -x 6_out.htm
}

get_key(){
###############################################
### Get single key input And pass to $key_input
###############################################
tput smso
tput rmso
oldstty=`stty -g`
stty -icanon -echo min 1 time 0
key_input=`dd bs=1 count=1 2>/dev/null`
stty "$oldstty"
# echo
}

key_input_1_4_0(){
###############################################
### Get Multiple Choice Input
###############################################
# Required header get_key() htm_out()
# Required variables $test1 $test2 $test3 $test4 $test5
# Passes to $key_input
#
# description1='Example of 1 through 4 or 0'
# htm_out
# test1='1'
# test1='2'
# test1='3'
# test1='4'
# test1='0'
# key_input_1_4_0
# description1=$key_input
# htm_out
#
# description1='Example of 1 through 5'
# htm_out
# test1='1'
# test1='2'
# test1='3'
# test1='4'
# test1='5'
# key_input_1_4_0
# description3=$key_input
# htm_out
#
# description1='Example of 1 through 3'
# htm_out
# test1='1'
# test1='2'
# test1='3'
# test1='3'
# test1='3'
# key_input_1_4_0
# description3=$key_input
# htm_out
###############################################
 description5=''
 key_input='xxx'
 testx='n'
 testy='y'
 testz='xxx'
 get_key
 while [ $testx != $testy ]; do
 if [ $key_input -eq $test1 ]; then
 description5=''
 testx='y'
 fi
 if [ $key_input -eq $test2 ]; then
 description5=''
 testx='y'
 fi
 if [ $key_input -eq $test3 ]; then
 description5=''
 testx='y'
 fi
 if [ $key_input -eq $test4 ]; then
 description5=''
 testx='y'
 fi
 if [ $key_input -eq $test5 ]; then
 description5=''
 testx='y'
 fi
 if [ $testx != $testy ]; then
 description5='That is not a valid input. Try again.'
 htm_out
 get_key
 fi
 done
 description5=''
}

key_input_y_n_0(){
###############################################
### Get Multiple Choice Input Y N or 0
###############################################
# Required header get_key() htm_out()
# Passes to $key_input
# Converts Y to 1
# Converts N to 4
# Condition 0 Remains 0
###############################################
 description5=''
 key_input='xxx'
 test3='0'
 testx='n'
 testy='y'
 testz='xxx'
 get_key
 while [ $testx != $testy ]; do
 if [ $key_input = 'y' ]; then
 key_input='1'
 description5=''
 testx='y'
 fi
 if [ $key_input = 'n' ]; then
 key_input='4'
 description5=''
 testx='y'
 fi
 if [ $key_input -eq $test3 ]; then
 description5=''
 testx='y'
 fi
 if [ $testx != $testy ]; then
 description5='That is not a valid input. Try again.'
 htm_out
 get_key
 fi
 done
 description5=''
}

key_input_y_n(){
###############################################
### Get Input Y or N
###############################################
# Required header get_key() htm_out()
# Passes to $key_input
# Condition y Remains y
# Condition n Remains n
###############################################
 description5=''
 key_input='xxx'
 testx='n'
 testy='y'
 testz='xxx'
 get_key

 while [ $testx != $testy ]; do
 if [ $key_input = 'y' ]; then
 description5=''
 testx='y'
 fi
 if [ $key_input = 'n' ]; then
 description5=''
 testx='y'
 fi
 if [ $testx != $testy ]; then
 description5='That is not a valid input. Try again.'
 htm_out
 get_key
 fi
 done
 description5=''
}

joec@home

Feb 9 2009, 01:17 AM

I am finding sometimes if you call random numbers from the same script multiple times that it repeats number. So I created a second file to be called from within a script

#/bin/bash
# Random Number Generator
# Example rand=`sh 4_random.sh 10`
# Will return a random number between 1 and 10 and store to $rand
range=$1
RANDOM=$$
rand=$((RANDOM%range+1))
val=$rand
echo $val
exit

Catalyst

Feb 11 2009, 11:07 AM

Uhh, not actually. It's semantically correct --- you assign a random number to a variable, and re-use the variable, it's always going to be the original variable. Simply redeclaring the variable will fix that.

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