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BASH validate user input


 
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# 1  
Old 07-27-2009
BASH validate user input

Hey, im trying to validate a user input and need some help. The input needs to be just a single letter. Im using a case to so this eg:

Code:
read answer
case $answer in
     [A-Za-z]*) echo "OK"
        ;;
     [0-9]*) echo "This is a number"
                read answer
        ;;
        *)   echo "Please enter a letter ! !"
              read answer
        ;;
esac

I need to stop multiple letters and repeat letters being entered. Any ideas?? Thanks for any help.
# 2  
Old 07-27-2009
this appears to be much the same as the question asked in

https://www.unix.com/unix-dummies-que...-alphabet.html

you guys doing the same course ;-)

And to answer your question...you could do it in a variety oif ways...maybe you could look at the length of the input...or use dd to "read" in one char at a time...etc
# 3  
Old 07-28-2009
Ha thanks, that sorted it out!
 

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