How do I prompt for Yes/No/Cancel input in a Linux shell script?

Question

I want to pause input in a shell script, and prompt the user for choices. The standard 'Yes, No, or Cancel' type question. How do I accomplish this in a typical bash prompt?

Answer 1

# I think read is command you're looking for: here is exmaple:

while true; do

read -p "Make a choice? Answer: yes/y, no/n, cancel/c " yn

case $yn in

[Yy]* ) echo "You made your choice"; break;;

[Cc]* ) echo "This operation is canceled"; exit;;

[Nn]* ) echo "Exit out"; exit;;

* ) echo "Please answer yes, cancel, or no.";;

esac

done

Answer 2

The python language has a built-in facility to prompt & read in one motion ...

Bash does not ... you kinda need to prompt, then read, using the "echo -n" and "read" functions.

See sample script and output below - it reflects the requirements you suggest in the question.

typeset -l ans ## forces lower case

prompt="Go Forward? (yes, no, cancel) : "

action=

ansFlag=0

while (( ansFlag == 0 )) ## keep prompting until the user gets it right ...

do

echo -n "$prompt"

read ans

case "$ans" in

"yes")

action="Yes Action"

ansFlag=1

;;

"no")

action="No Action"

ansFlag=1

;;

"cancel")

action="Action Action"

ansFlag=1

;;

*)

echo "Invalid Response" >&2

;;

esac

done

echo "Performing: $action"

exit 0

And this is a sample interaction with the script ...

$ ./readit

Go Forward? (yes, no, cancel) :

Invalid Response

Go Forward? (yes, no, cancel) : kjkj

Invalid Response

Go Forward? (yes, no, cancel) : yes

Performing: Yes Action