Shell Programming and Scripting

# sourced from a configuration file, we have a lot of options
opt_1="My file"
opt_2="My option"
opt_3="My variable..."

# then we use a gui to request the new value, which will return:
form="New File Name|option 2|option 3"

x=1
printf "$form\n" | sed 's/|/\n/g' | while read option; do
    export opt_$x="$option" # we use export, which works with other scripts
    x=$((x+1))
done

for number in $(seq 1 3); do
    opt=opt_$number
    echo "$opt=${!opt}" # ${!opt} returns the old value, not the new exported!
done

$ value=hello
$ greeting=value
$ echo $greeting
value
$ echo ${!greeting}
hello

# count lines in output from ps command
var=1
ps -ef | while read x
do
        var=$(( $var + 1 ))
done
echo $var

$ ksh t22
126
$ bash t22
1

opt=opt_$number
echo "$opt=${!opt}"

opt_$number=${!opt_$number} # which of course won't work

eval opt_$number=\${!opt_$number}

exec 3> >(application)

command |&