Stuck in a while-loop in GNU/SU (seismic unix)

Question

I'm new to programming. I have this loop (it's part of a data processing script) and I have it all good until this section cause I can't figure out why it stay looping in the second 'while'

Take a look:

.../bash
cdpmin=1800
cdpmax=2100
dcdp=100
cdp=$cdpmin

while [ $cdp -le $cdpmax ]
do
echo $cdp
ok=false

while [ ok=false ]
do
.
.
.
echo "It's correct? (y/n)" | tr -d "\012" >/dev/tty
read response

case $response in  
    n*)   
       ok=false ;;  
    *)   
       ok=true ;;  
esac   

done

cdp=$[$cdp+$dcdp]

done

Thanks a lot

Answer 1

You aren't comparing what you think you are, you are comparing the literal "ok" with the word "false". Instead, you need to compare the variable $ok with false.

With that adjustment, it would look like:

ok="false"
while [[ "$ok" = "false" ]]
do
    ...
done

I believe you will also run into an error with cdp=$[$cdp + $dcpd], in bash, addition usually looks like:

cdp=$(($cdp + $dcpd))

A tip: Since the condition for the loop you were stuck in was ok=false, it is clear that the issue is in the condition not changing as you expect. This is one of those easy to overlook issues though that is a face palm after the fact. Any time I run into these, I go for a walk or something to take my mind off it. More often than not, when I come back - the issue is obvious.