Apply Regex to input read


 
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# 1  
Apply Regex to input read

Hi I am very new to Unix Shell. I have a question:

How do you check the input value against a reqex?

For example using korn Shell:

Code:
echo "Please enter revision month: \c"
read revmon

if $revmon | egrep -c = '[A-Z]{3}[0-9]{2}"'

then
echo "OK"
else

echo "PLease re-enter a valid revision month (e.g. SEP07)"

fi

# 2  
With the Korn Shell you can use this:

Code:
print -n "Please enter revision month: "
read; case $REPLY in
([A-Z][A-Z][A-Z][0-9][0-9])print OK;;
(*)print KO;;
esac

P.S. In ths case it's globbing, not RE's.

Last edited by radoulov; 09-23-2007 at 01:51 PM.. Reason: addition
# 3  
Thanks... it worked perfect.

BTW what does esac mean?
# 4  
The letters of the word case reversed Smilie
 

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